Remove MachInst::gen_constant (#5427)

* aarch64: constant generation cleanup

Add support for MOVZ and MOVN generation via ISLE.
Handle f32const, f64const, and nop instructions via ISLE.
No longer call Inst::gen_constant from lower.rs.

* riscv64: constant generation cleanup

Handle f32const, f64const, and nop instructions via ISLE.

* s390x: constant generation cleanup

Fix rule priorities for "imm" term.
Only handle 32-bit stack offsets; no longer use load_constant64.

* x64: constant generation cleanup

No longer call Inst::gen_constant from lower.rs or abi.rs.

* Refactor LowerBackend::lower to return InstOutput

No longer write to the per-insn output registers; instead, return
an InstOutput vector of temp registers holding the outputs.

This will allow calling LowerBackend::lower multiple times for
the same instruction, e.g. to rematerialize constants.

When emitting the primary copy of the instruction during lowering,
writing to the per-insn registers is now done in lower_clif_block.

As a result, the ISLE lower_common routine is no longer needed.
In addition, the InsnOutput type and all code related to it
can be removed as well.

* Refactor IsleContext to hold a LowerBackend reference

Remove the "triple", "flags", and "isa_flags" fields that are
copied from LowerBackend to each IsleContext, and instead just
hold a reference to LowerBackend in IsleContext.

This will allow calling LowerBackend::lower from within callbacks
in src/machinst/isle.rs, e.g. to rematerialize constants.

To avoid having to pass LowerBackend references through multiple
functions, eliminate the lower_insn_to_regs subroutines in those
targets that still have them, and just inline into the main
lower routine.  This also eliminates lower_inst.rs on aarch64
and riscv64.

Replace all accesses to the removed IsleContext fields by going
through the LowerBackend reference.

* Remove MachInst::gen_constant

This addresses the problem described in issue
https://github.com/bytecodealliance/wasmtime/issues/4426
that targets currently have to duplicate code to emit
constants between the ISLE logic and the gen_constant
callback.

After the various cleanups in earlier patches in this series,
the only remaining user of get_constant is put_value_in_regs
in Lower.  This can now be removed, and instead constant
rematerialization can be performed in the put_in_regs ISLE
callback by simply directly calling LowerBackend::lower
on the instruction defining the constant (using a different
output register).

Since the check for egraph mode is now no longer performed in
put_value_in_regs, the Lower::flags member becomes obsolete.

Care needs to be taken that other calls directly to the
Lower::put_value_in_regs routine now handle the fact that
no more rematerialization is performed.  All such calls in
target code already historically handle constants themselves.
The remaining call site in the ISLE gen_call_common helper
can be redirected to the ISLE put_in_regs callback.

The existing target implementations of gen_constant are then
unused and can be removed.  (In some target there may still
be further opportunities to remove duplication between ISLE
and some local Rust code - this can be left to future patches.)

cranelift/codegen/src/isa/aarch64/inst.isle

@@ -1607,6 +1607,12 @@
 
 ;; Extractor helpers for various immmediate constants ;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(decl pure partial move_wide_const_from_u64 (Type u64) MoveWideConst)
+(extern constructor move_wide_const_from_u64 move_wide_const_from_u64)
+
+(decl pure partial move_wide_const_from_inverted_u64 (Type u64) MoveWideConst)
+(extern constructor move_wide_const_from_inverted_u64 move_wide_const_from_inverted_u64)
+
 (decl pure partial imm_logic_from_u64 (Type u64) ImmLogic)
 (extern constructor imm_logic_from_u64 imm_logic_from_u64)
 
@@ -2747,6 +2753,15 @@
 ;; such as `I8` are either sign- or zero-extended.
 (decl imm (Type ImmExtend u64) Reg)
 
+;; Move wide immediate instructions; to simplify, we only match when we
+;; are zero-extending the value.
+(rule 3 (imm (integral_ty ty) (ImmExtend.Zero) k)
+      (if-let n (move_wide_const_from_u64 ty k))
+      (movz n (operand_size ty)))
+(rule 2 (imm (integral_ty (ty_32_or_64 ty)) (ImmExtend.Zero) k)
+      (if-let n (move_wide_const_from_inverted_u64 ty k))
+      (movn n (operand_size ty)))
+
 ;; Weird logical-instruction immediate in ORI using zero register; to simplify,
 ;; we only match when we are zero-extending the value.
 (rule 1 (imm (integral_ty ty) (ImmExtend.Zero) k)
@@ -2940,6 +2955,11 @@
       (let ((_ Unit (sink_inst x)))
            (amode ty addr offset)))
 
+;; Lower a constant f32.
+(decl constant_f32 (u64) Reg)
+;; TODO: Port lower_constant_f32() to ISLE.
+(extern constructor constant_f32 constant_f32)
+
 ;; Lower a constant f64.
 (decl constant_f64 (u64) Reg)
 ;; TODO: Port lower_constant_f64() to ISLE.

cranelift/codegen/src/isa/aarch64/inst/mod.rs

@@ -234,27 +234,6 @@ impl Inst {
         }
     }
 
-    /// Create instructions that load a 128-bit constant.
-    pub fn load_constant128<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        mut alloc_tmp: F,
-    ) -> SmallVec<[Inst; 4]> {
-        assert_eq!(to_regs.len(), 2, "Expected to load i128 into two registers");
-
-        let lower = value as u64;
-        let upper = (value >> 64) as u64;
-
-        let lower_reg = to_regs.regs()[0];
-        let upper_reg = to_regs.regs()[1];
-
-        let mut load_ins = Inst::load_constant(lower_reg, lower, &mut alloc_tmp);
-        let load_upper = Inst::load_constant(upper_reg, upper, &mut alloc_tmp);
-
-        load_ins.extend(load_upper.into_iter());
-        load_ins
-    }
-
     /// Create instructions that load a 32-bit floating-point constant.
     pub fn load_fp_constant32<F: FnMut(Type) -> Writable<Reg>>(
         rd: Writable<Reg>,
@@ -1233,24 +1212,6 @@ impl MachInst for Inst {
         }
     }
 
-    fn gen_constant<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        ty: Type,
-        mut alloc_tmp: F,
-    ) -> SmallVec<[Inst; 4]> {
-        let to_reg = to_regs.only_reg();
-        match ty {
-            F64 => Inst::load_fp_constant64(to_reg.unwrap(), value as u64, alloc_tmp),
-            F32 => Inst::load_fp_constant32(to_reg.unwrap(), value as u32, alloc_tmp),
-            I8 | I16 | I32 | I64 | R32 | R64 => {
-                Inst::load_constant(to_reg.unwrap(), value as u64, &mut alloc_tmp)
-            }
-            I128 => Inst::load_constant128(to_regs, value, alloc_tmp),
-            _ => panic!("Cannot generate constant for type: {}", ty),
-        }
-    }
-
     fn gen_dummy_use(reg: Reg) -> Inst {
         Inst::DummyUse { reg }
     }

cranelift/codegen/src/isa/aarch64/lower.isle

@@ -24,6 +24,21 @@
 (rule (lower (has_type ty (null)))
       (imm ty (ImmExtend.Zero) 0))
 
+;;;; Rules for `f32const` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(rule (lower (f32const (u64_from_ieee32 n)))
+      (constant_f32 n))
+
+;;;; Rules for `f64const` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(rule (lower (f64const (u64_from_ieee64 n)))
+      (constant_f64 n))
+
+;;;; Rules for `nop` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(rule (lower (nop))
+      (invalid_reg))
+
 ;;;; Rules for `iadd` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 ;; `i64` and smaller

cranelift/codegen/src/isa/aarch64/lower.rs

@@ -7,7 +7,6 @@
 //!
 //! - Floating-point immediates (FIMM instruction).
 
-use super::lower_inst;
 use crate::ir::condcodes::{FloatCC, IntCC};
 use crate::ir::types::*;
 use crate::ir::Inst as IRInst;
@@ -16,6 +15,7 @@ use crate::isa::aarch64::inst::*;
 use crate::isa::aarch64::AArch64Backend;
 use crate::machinst::lower::*;
 use crate::machinst::{Reg, Writable};
+use crate::CodegenError;
 use crate::CodegenResult;
 use crate::{machinst::*, trace};
 use smallvec::{smallvec, SmallVec};
@@ -43,27 +43,6 @@ impl NarrowValueMode {
     }
 }
 
-/// Emits instruction(s) to generate the given constant value into newly-allocated
-/// temporary registers, returning these registers.
-fn generate_constant(ctx: &mut Lower<Inst>, ty: Type, c: u128) -> ValueRegs<Reg> {
-    let from_bits = ty_bits(ty);
-    let masked = if from_bits < 128 {
-        c & ((1u128 << from_bits) - 1)
-    } else {
-        c
-    };
-
-    let cst_copy = ctx.alloc_tmp(ty);
-    for inst in Inst::gen_constant(cst_copy, masked, ty, |ty| {
-        ctx.alloc_tmp(ty).only_reg().unwrap()
-    })
-    .into_iter()
-    {
-        ctx.emit(inst);
-    }
-    non_writable_value_regs(cst_copy)
-}
-
 /// Extends a register according to `narrow_mode`.
 /// If extended, the value is always extended to 64 bits, for simplicity.
 fn extend_reg(
@@ -112,7 +91,20 @@ fn lower_value_to_regs(ctx: &mut Lower<Inst>, value: Value) -> (ValueRegs<Reg>,
 
     let in_regs = if let Some(c) = inputs.constant {
         // Generate constants fresh at each use to minimize long-range register pressure.
-        generate_constant(ctx, ty, c as u128)
+        let from_bits = ty_bits(ty);
+        let c = if from_bits < 64 {
+            c & ((1u64 << from_bits) - 1)
+        } else {
+            c
+        };
+        match ty {
+            I8 | I16 | I32 | I64 | R32 | R64 => {
+                let cst_copy = ctx.alloc_tmp(ty);
+                lower_constant_u64(ctx, cst_copy.only_reg().unwrap(), c);
+                non_writable_value_regs(cst_copy)
+            }
+            _ => unreachable!(), // Only used for addresses.
+        }
     } else {
         ctx.put_value_in_regs(value)
     };
@@ -754,8 +746,227 @@ pub(crate) fn maybe_value_multi(
 impl LowerBackend for AArch64Backend {
     type MInst = Inst;
 
-    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<()> {
+    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<InstOutput> {
-        lower_inst::lower_insn_to_regs(ctx, ir_inst, &self.triple, &self.flags, &self.isa_flags)
+        if let Some(temp_regs) = super::lower::isle::lower(ctx, self, ir_inst) {
+            return Ok(temp_regs);
+        }
+
+        let op = ctx.data(ir_inst).opcode();
+        let ty = if ctx.num_outputs(ir_inst) > 0 {
+            Some(ctx.output_ty(ir_inst, 0))
+        } else {
+            None
+        };
+
+        match op {
+            Opcode::Iconst
+            | Opcode::Null
+            | Opcode::F32const
+            | Opcode::F64const
+            | Opcode::GetFramePointer
+            | Opcode::GetStackPointer
+            | Opcode::GetReturnAddress
+            | Opcode::Iadd
+            | Opcode::Isub
+            | Opcode::UaddSat
+            | Opcode::SaddSat
+            | Opcode::UsubSat
+            | Opcode::SsubSat
+            | Opcode::Ineg
+            | Opcode::Imul
+            | Opcode::Umulhi
+            | Opcode::Smulhi
+            | Opcode::Udiv
+            | Opcode::Sdiv
+            | Opcode::Urem
+            | Opcode::Srem
+            | Opcode::Uextend
+            | Opcode::Sextend
+            | Opcode::Bnot
+            | Opcode::Band
+            | Opcode::Bor
+            | Opcode::Bxor
+            | Opcode::BandNot
+            | Opcode::BorNot
+            | Opcode::BxorNot
+            | Opcode::Ishl
+            | Opcode::Ushr
+            | Opcode::Sshr
+            | Opcode::Rotr
+            | Opcode::Rotl
+            | Opcode::Bitrev
+            | Opcode::Clz
+            | Opcode::Cls
+            | Opcode::Ctz
+            | Opcode::Bswap
+            | Opcode::Popcnt
+            | Opcode::Load
+            | Opcode::Uload8
+            | Opcode::Sload8
+            | Opcode::Uload16
+            | Opcode::Sload16
+            | Opcode::Uload32
+            | Opcode::Sload32
+            | Opcode::Sload8x8
+            | Opcode::Uload8x8
+            | Opcode::Sload16x4
+            | Opcode::Uload16x4
+            | Opcode::Sload32x2
+            | Opcode::Uload32x2
+            | Opcode::Store
+            | Opcode::Istore8
+            | Opcode::Istore16
+            | Opcode::Istore32
+            | Opcode::StackAddr
+            | Opcode::DynamicStackAddr
+            | Opcode::AtomicRmw
+            | Opcode::AtomicCas
+            | Opcode::AtomicLoad
+            | Opcode::AtomicStore
+            | Opcode::Fence
+            | Opcode::Nop
+            | Opcode::Select
+            | Opcode::SelectSpectreGuard
+            | Opcode::Bitselect
+            | Opcode::Vselect
+            | Opcode::IsNull
+            | Opcode::IsInvalid
+            | Opcode::Ireduce
+            | Opcode::Bmask
+            | Opcode::Bitcast
+            | Opcode::Return
+            | Opcode::Icmp
+            | Opcode::Fcmp
+            | Opcode::Debugtrap
+            | Opcode::Trap
+            | Opcode::ResumableTrap
+            | Opcode::FuncAddr
+            | Opcode::SymbolValue
+            | Opcode::Call
+            | Opcode::CallIndirect
+            | Opcode::GetPinnedReg
+            | Opcode::SetPinnedReg
+            | Opcode::Vconst
+            | Opcode::Extractlane
+            | Opcode::Insertlane
+            | Opcode::Splat
+            | Opcode::ScalarToVector
+            | Opcode::VallTrue
+            | Opcode::VanyTrue
+            | Opcode::VhighBits
+            | Opcode::Shuffle
+            | Opcode::Swizzle
+            | Opcode::Isplit
+            | Opcode::Iconcat
+            | Opcode::Smax
+            | Opcode::Umax
+            | Opcode::Umin
+            | Opcode::Smin
+            | Opcode::IaddPairwise
+            | Opcode::WideningPairwiseDotProductS
+            | Opcode::Fadd
+            | Opcode::Fsub
+            | Opcode::Fmul
+            | Opcode::Fdiv
+            | Opcode::Fmin
+            | Opcode::Fmax
+            | Opcode::FminPseudo
+            | Opcode::FmaxPseudo
+            | Opcode::Sqrt
+            | Opcode::Fneg
+            | Opcode::Fabs
+            | Opcode::Fpromote
+            | Opcode::Fdemote
+            | Opcode::Ceil
+            | Opcode::Floor
+            | Opcode::Trunc
+            | Opcode::Nearest
+            | Opcode::Fma
+            | Opcode::Fcopysign
+            | Opcode::FcvtToUint
+            | Opcode::FcvtToSint
+            | Opcode::FcvtFromUint
+            | Opcode::FcvtFromSint
+            | Opcode::FcvtToUintSat
+            | Opcode::FcvtToSintSat
+            | Opcode::UaddOverflowTrap
+            | Opcode::IaddCout
+            | Opcode::Iabs
+            | Opcode::AvgRound
+            | Opcode::Snarrow
+            | Opcode::Unarrow
+            | Opcode::Uunarrow
+            | Opcode::SwidenLow
+            | Opcode::SwidenHigh
+            | Opcode::UwidenLow
+            | Opcode::UwidenHigh
+            | Opcode::TlsValue
+            | Opcode::SqmulRoundSat
+            | Opcode::FcvtLowFromSint
+            | Opcode::FvpromoteLow
+            | Opcode::Fvdemote
+            | Opcode::ExtractVector => {
+                unreachable!(
+                    "implemented in ISLE: inst = `{}`, type = `{:?}`",
+                    ctx.dfg().display_inst(ir_inst),
+                    ty
+                );
+            }
+
+            Opcode::StackLoad
+            | Opcode::StackStore
+            | Opcode::DynamicStackStore
+            | Opcode::DynamicStackLoad => {
+                panic!("Direct stack memory access not supported; should not be used by Wasm");
+            }
+            Opcode::HeapLoad | Opcode::HeapStore | Opcode::HeapAddr => {
+                panic!("heap access instructions should have been removed by legalization!");
+            }
+            Opcode::TableAddr => {
+                panic!("table_addr should have been removed by legalization!");
+            }
+            Opcode::Trapz | Opcode::Trapnz | Opcode::ResumableTrapnz => {
+                panic!(
+                    "trapz / trapnz / resumable_trapnz should have been removed by legalization!"
+                );
+            }
+            Opcode::GlobalValue => {
+                panic!("global_value should have been removed by legalization!");
+            }
+            Opcode::Jump | Opcode::Brz | Opcode::Brnz | Opcode::BrTable => {
+                panic!("Branch opcode reached non-branch lowering logic!");
+            }
+            Opcode::IaddImm
+            | Opcode::ImulImm
+            | Opcode::UdivImm
+            | Opcode::SdivImm
+            | Opcode::UremImm
+            | Opcode::SremImm
+            | Opcode::IrsubImm
+            | Opcode::IaddCin
+            | Opcode::IaddCarry
+            | Opcode::IsubBin
+            | Opcode::IsubBout
+            | Opcode::IsubBorrow
+            | Opcode::BandImm
+            | Opcode::BorImm
+            | Opcode::BxorImm
+            | Opcode::RotlImm
+            | Opcode::RotrImm
+            | Opcode::IshlImm
+            | Opcode::UshrImm
+            | Opcode::SshrImm
+            | Opcode::IcmpImm => {
+                panic!("ALU+imm and ALU+carry ops should not appear here!");
+            }
+
+            Opcode::Vconcat | Opcode::Vsplit => {
+                return Err(CodegenError::Unsupported(format!(
+                    "Unimplemented lowering: {}",
+                    op
+                )));
+            }
+        }
     }
 
     fn lower_branch_group(
@@ -776,14 +987,8 @@ impl LowerBackend for AArch64Backend {
             assert!(op1 == Opcode::Jump);
         }
 
-        if let Ok(()) = super::lower::isle::lower_branch(
+        if let Some(temp_regs) = super::lower::isle::lower_branch(ctx, self, branches[0], targets) {
-            ctx,
+            assert!(temp_regs.len() == 0);
-            &self.triple,
-            &self.flags,
-            &self.isa_flags,
-            branches[0],
-            targets,
-        ) {
             return Ok(());
         }
 

cranelift/codegen/src/isa/aarch64/lower/isle.rs

@@ -18,10 +18,9 @@ use super::{
 use crate::ir::condcodes;
 use crate::isa::aarch64::inst::{FPULeftShiftImm, FPURightShiftImm};
 use crate::isa::aarch64::lower::{lower_address, lower_pair_address, lower_splat_const};
-use crate::isa::aarch64::settings::Flags as IsaFlags;
+use crate::isa::aarch64::AArch64Backend;
 use crate::machinst::valueregs;
 use crate::machinst::{isle::*, InputSourceInst};
-use crate::settings::Flags;
 use crate::{
     binemit::CodeOffset,
     ir::{
@@ -32,7 +31,7 @@ use crate::{
     isa::aarch64::inst::args::{ShiftOp, ShiftOpShiftImm},
     isa::unwind::UnwindInst,
     machinst::{
-        abi::ArgPair, ty_bits, InsnOutput, Lower, MachInst, VCodeConstant, VCodeConstantData,
+        abi::ArgPair, ty_bits, InstOutput, Lower, MachInst, VCodeConstant, VCodeConstantData,
     },
 };
 use crate::{isle_common_prelude_methods, isle_lower_prelude_methods};
@@ -40,7 +39,6 @@ use regalloc2::PReg;
 use std::boxed::Box;
 use std::convert::TryFrom;
 use std::vec::Vec;
-use target_lexicon::Triple;
 
 type BoxCallInfo = Box<CallInfo>;
 type BoxCallIndInfo = Box<CallIndInfo>;
@@ -52,40 +50,25 @@ type VecArgPair = Vec<ArgPair>;
 /// The main entry point for lowering with ISLE.
 pub(crate) fn lower(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &AArch64Backend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
-    outputs: &[InsnOutput],
     inst: Inst,
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower(&mut isle_ctx, inst)
-        isa_flags,
-        outputs,
-        inst,
-        |cx, insn| generated_code::constructor_lower(cx, insn),
-    )
 }
 
 pub(crate) fn lower_branch(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &AArch64Backend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
     branch: Inst,
     targets: &[MachLabel],
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower_branch(&mut isle_ctx, branch, &targets.to_vec())
-        isa_flags,
-        &[],
-        branch,
-        |cx, insn| generated_code::constructor_lower_branch(cx, insn, &targets.to_vec()),
-    )
 }
 
 pub struct ExtendedValue {
@@ -93,16 +76,16 @@ pub struct ExtendedValue {
     extend: ExtendOp,
 }
 
-impl IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl IsleContext<'_, '_, MInst, AArch64Backend> {
     isle_prelude_method_helpers!(AArch64Caller);
 }
 
-impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl Context for IsleContext<'_, '_, MInst, AArch64Backend> {
     isle_lower_prelude_methods!();
     isle_prelude_caller_methods!(crate::isa::aarch64::abi::AArch64MachineDeps, AArch64Caller);
 
     fn sign_return_address_disabled(&mut self) -> Option<()> {
-        if self.isa_flags.sign_return_address() {
+        if self.backend.isa_flags.sign_return_address() {
             None
         } else {
             Some(())
@@ -110,13 +93,27 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
     }
 
     fn use_lse(&mut self, _: Inst) -> Option<()> {
-        if self.isa_flags.has_lse() {
+        if self.backend.isa_flags.has_lse() {
             Some(())
         } else {
             None
         }
     }
 
+    fn move_wide_const_from_u64(&mut self, ty: Type, n: u64) -> Option<MoveWideConst> {
+        let bits = ty.bits();
+        let n = if bits < 64 {
+            n & !(u64::MAX << bits)
+        } else {
+            n
+        };
+        MoveWideConst::maybe_from_u64(n)
+    }
+
+    fn move_wide_const_from_inverted_u64(&mut self, ty: Type, n: u64) -> Option<MoveWideConst> {
+        self.move_wide_const_from_u64(ty, !n)
+    }
+
     fn imm_logic_from_u64(&mut self, ty: Type, n: u64) -> Option<ImmLogic> {
         ImmLogic::maybe_from_u64(n, ty)
     }
@@ -523,6 +520,14 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
         lower_pair_address(self.lower_ctx, addr, offset as i32)
     }
 
+    fn constant_f32(&mut self, value: u64) -> Reg {
+        let rd = self.temp_writable_reg(I8X16);
+
+        lower_constant_f32(self.lower_ctx, rd, f32::from_bits(value as u32));
+
+        rd.to_reg()
+    }
+
     fn constant_f64(&mut self, value: u64) -> Reg {
         let rd = self.temp_writable_reg(I8X16);
 

cranelift/codegen/src/isa/aarch64/lower_inst.rs

@@ -1,306 +0,0 @@
-//! Lower a single Cranelift instruction into vcode.
-
-use crate::ir::Inst as IRInst;
-use crate::ir::Opcode;
-use crate::isa::aarch64::inst::*;
-use crate::isa::aarch64::settings as aarch64_settings;
-use crate::machinst::lower::*;
-use crate::machinst::*;
-use crate::settings::Flags;
-use crate::{CodegenError, CodegenResult};
-use target_lexicon::Triple;
-
-/// Actually codegen an instruction's results into registers.
-pub(crate) fn lower_insn_to_regs(
-    ctx: &mut Lower<Inst>,
-    insn: IRInst,
-    triple: &Triple,
-    flags: &Flags,
-    isa_flags: &aarch64_settings::Flags,
-) -> CodegenResult<()> {
-    let op = ctx.data(insn).opcode();
-    let outputs = insn_outputs(ctx, insn);
-    let ty = if outputs.len() > 0 {
-        Some(ctx.output_ty(insn, 0))
-    } else {
-        None
-    };
-
-    if let Ok(()) = super::lower::isle::lower(ctx, triple, flags, isa_flags, &outputs, insn) {
-        return Ok(());
-    }
-
-    let implemented_in_isle = |ctx: &mut Lower<Inst>| -> ! {
-        unreachable!(
-            "implemented in ISLE: inst = `{}`, type = `{:?}`",
-            ctx.dfg().display_inst(insn),
-            ty
-        );
-    };
-
-    match op {
-        Opcode::Iconst | Opcode::Null => implemented_in_isle(ctx),
-
-        Opcode::F32const => {
-            let rd = get_output_reg(ctx, outputs[0]).only_reg().unwrap();
-            let val = ctx.get_constant(insn).unwrap();
-            for inst in
-                Inst::load_fp_constant32(rd, val as u32, |ty| ctx.alloc_tmp(ty).only_reg().unwrap())
-            {
-                ctx.emit(inst);
-            }
-        }
-
-        Opcode::F64const => {
-            let rd = get_output_reg(ctx, outputs[0]).only_reg().unwrap();
-            let val = ctx.get_constant(insn).unwrap();
-            for inst in
-                Inst::load_fp_constant64(rd, val, |ty| ctx.alloc_tmp(ty).only_reg().unwrap())
-            {
-                ctx.emit(inst);
-            }
-        }
-
-        Opcode::GetFramePointer | Opcode::GetStackPointer | Opcode::GetReturnAddress => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::Iadd => implemented_in_isle(ctx),
-        Opcode::Isub => implemented_in_isle(ctx),
-        Opcode::UaddSat | Opcode::SaddSat | Opcode::UsubSat | Opcode::SsubSat => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::Ineg => implemented_in_isle(ctx),
-
-        Opcode::Imul => implemented_in_isle(ctx),
-
-        Opcode::Umulhi | Opcode::Smulhi => implemented_in_isle(ctx),
-
-        Opcode::Udiv | Opcode::Sdiv | Opcode::Urem | Opcode::Srem => implemented_in_isle(ctx),
-
-        Opcode::Uextend | Opcode::Sextend => implemented_in_isle(ctx),
-
-        Opcode::Bnot => implemented_in_isle(ctx),
-
-        Opcode::Band
-        | Opcode::Bor
-        | Opcode::Bxor
-        | Opcode::BandNot
-        | Opcode::BorNot
-        | Opcode::BxorNot => implemented_in_isle(ctx),
-
-        Opcode::Ishl | Opcode::Ushr | Opcode::Sshr => implemented_in_isle(ctx),
-
-        Opcode::Rotr | Opcode::Rotl => implemented_in_isle(ctx),
-
-        Opcode::Bitrev | Opcode::Clz | Opcode::Cls | Opcode::Ctz => implemented_in_isle(ctx),
-
-        Opcode::Bswap => implemented_in_isle(ctx),
-
-        Opcode::Popcnt => implemented_in_isle(ctx),
-
-        Opcode::Load
-        | Opcode::Uload8
-        | Opcode::Sload8
-        | Opcode::Uload16
-        | Opcode::Sload16
-        | Opcode::Uload32
-        | Opcode::Sload32
-        | Opcode::Sload8x8
-        | Opcode::Uload8x8
-        | Opcode::Sload16x4
-        | Opcode::Uload16x4
-        | Opcode::Sload32x2
-        | Opcode::Uload32x2 => implemented_in_isle(ctx),
-
-        Opcode::Store | Opcode::Istore8 | Opcode::Istore16 | Opcode::Istore32 => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::StackAddr => implemented_in_isle(ctx),
-
-        Opcode::DynamicStackAddr => implemented_in_isle(ctx),
-
-        Opcode::AtomicRmw => implemented_in_isle(ctx),
-
-        Opcode::AtomicCas => implemented_in_isle(ctx),
-
-        Opcode::AtomicLoad => implemented_in_isle(ctx),
-
-        Opcode::AtomicStore => implemented_in_isle(ctx),
-
-        Opcode::Fence => implemented_in_isle(ctx),
-
-        Opcode::StackLoad
-        | Opcode::StackStore
-        | Opcode::DynamicStackStore
-        | Opcode::DynamicStackLoad => {
-            panic!("Direct stack memory access not supported; should not be used by Wasm");
-        }
-
-        Opcode::HeapLoad | Opcode::HeapStore | Opcode::HeapAddr => {
-            panic!("heap access instructions should have been removed by legalization!");
-        }
-
-        Opcode::TableAddr => {
-            panic!("table_addr should have been removed by legalization!");
-        }
-
-        Opcode::Nop => {
-            // Nothing.
-        }
-
-        Opcode::Select => implemented_in_isle(ctx),
-
-        Opcode::SelectSpectreGuard => implemented_in_isle(ctx),
-
-        Opcode::Bitselect | Opcode::Vselect => implemented_in_isle(ctx),
-
-        Opcode::IsNull | Opcode::IsInvalid => implemented_in_isle(ctx),
-
-        Opcode::Ireduce => implemented_in_isle(ctx),
-
-        Opcode::Bmask => implemented_in_isle(ctx),
-
-        Opcode::Bitcast => implemented_in_isle(ctx),
-
-        Opcode::Return => implemented_in_isle(ctx),
-
-        Opcode::Icmp => implemented_in_isle(ctx),
-
-        Opcode::Fcmp => implemented_in_isle(ctx),
-
-        Opcode::Debugtrap => implemented_in_isle(ctx),
-
-        Opcode::Trap | Opcode::ResumableTrap => implemented_in_isle(ctx),
-
-        Opcode::Trapz | Opcode::Trapnz | Opcode::ResumableTrapnz => {
-            panic!("trapz / trapnz / resumable_trapnz should have been removed by legalization!");
-        }
-
-        Opcode::FuncAddr => implemented_in_isle(ctx),
-
-        Opcode::GlobalValue => {
-            panic!("global_value should have been removed by legalization!");
-        }
-
-        Opcode::SymbolValue => implemented_in_isle(ctx),
-
-        Opcode::Call | Opcode::CallIndirect => implemented_in_isle(ctx),
-
-        Opcode::GetPinnedReg | Opcode::SetPinnedReg => implemented_in_isle(ctx),
-
-        Opcode::Jump | Opcode::Brz | Opcode::Brnz | Opcode::BrTable => {
-            panic!("Branch opcode reached non-branch lowering logic!");
-        }
-
-        Opcode::Vconst => implemented_in_isle(ctx),
-
-        Opcode::Extractlane => implemented_in_isle(ctx),
-
-        Opcode::Insertlane => implemented_in_isle(ctx),
-
-        Opcode::Splat => implemented_in_isle(ctx),
-
-        Opcode::ScalarToVector => implemented_in_isle(ctx),
-
-        Opcode::VallTrue | Opcode::VanyTrue => implemented_in_isle(ctx),
-
-        Opcode::VhighBits => implemented_in_isle(ctx),
-
-        Opcode::Shuffle => implemented_in_isle(ctx),
-
-        Opcode::Swizzle => implemented_in_isle(ctx),
-
-        Opcode::Isplit => implemented_in_isle(ctx),
-
-        Opcode::Iconcat => implemented_in_isle(ctx),
-
-        Opcode::Smax | Opcode::Umax | Opcode::Umin | Opcode::Smin => implemented_in_isle(ctx),
-
-        Opcode::IaddPairwise => implemented_in_isle(ctx),
-
-        Opcode::WideningPairwiseDotProductS => implemented_in_isle(ctx),
-
-        Opcode::Fadd | Opcode::Fsub | Opcode::Fmul | Opcode::Fdiv | Opcode::Fmin | Opcode::Fmax => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::FminPseudo | Opcode::FmaxPseudo => implemented_in_isle(ctx),
-
-        Opcode::Sqrt | Opcode::Fneg | Opcode::Fabs | Opcode::Fpromote | Opcode::Fdemote => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::Ceil | Opcode::Floor | Opcode::Trunc | Opcode::Nearest => implemented_in_isle(ctx),
-
-        Opcode::Fma => implemented_in_isle(ctx),
-
-        Opcode::Fcopysign => implemented_in_isle(ctx),
-
-        Opcode::FcvtToUint | Opcode::FcvtToSint => implemented_in_isle(ctx),
-
-        Opcode::FcvtFromUint | Opcode::FcvtFromSint => implemented_in_isle(ctx),
-
-        Opcode::FcvtToUintSat | Opcode::FcvtToSintSat => implemented_in_isle(ctx),
-
-        Opcode::UaddOverflowTrap => implemented_in_isle(ctx),
-
-        Opcode::IaddCout => implemented_in_isle(ctx),
-
-        Opcode::IaddImm
-        | Opcode::ImulImm
-        | Opcode::UdivImm
-        | Opcode::SdivImm
-        | Opcode::UremImm
-        | Opcode::SremImm
-        | Opcode::IrsubImm
-        | Opcode::IaddCin
-        | Opcode::IaddCarry
-        | Opcode::IsubBin
-        | Opcode::IsubBout
-        | Opcode::IsubBorrow
-        | Opcode::BandImm
-        | Opcode::BorImm
-        | Opcode::BxorImm
-        | Opcode::RotlImm
-        | Opcode::RotrImm
-        | Opcode::IshlImm
-        | Opcode::UshrImm
-        | Opcode::SshrImm
-        | Opcode::IcmpImm => {
-            panic!("ALU+imm and ALU+carry ops should not appear here!");
-        }
-
-        Opcode::Iabs => implemented_in_isle(ctx),
-        Opcode::AvgRound => implemented_in_isle(ctx),
-
-        Opcode::Snarrow | Opcode::Unarrow | Opcode::Uunarrow => implemented_in_isle(ctx),
-
-        Opcode::SwidenLow | Opcode::SwidenHigh | Opcode::UwidenLow | Opcode::UwidenHigh => {
-            implemented_in_isle(ctx)
-        }
-
-        Opcode::TlsValue => implemented_in_isle(ctx),
-
-        Opcode::SqmulRoundSat => implemented_in_isle(ctx),
-
-        Opcode::FcvtLowFromSint => implemented_in_isle(ctx),
-
-        Opcode::FvpromoteLow => implemented_in_isle(ctx),
-
-        Opcode::Fvdemote => implemented_in_isle(ctx),
-
-        Opcode::ExtractVector => implemented_in_isle(ctx),
-
-        Opcode::Vconcat | Opcode::Vsplit => {
-            return Err(CodegenError::Unsupported(format!(
-                "Unimplemented lowering: {}",
-                op
-            )));
-        }
-    }
-
-    Ok(())
-}

cranelift/codegen/src/isa/aarch64/mod.rs

@@ -21,7 +21,6 @@ use target_lexicon::{Aarch64Architecture, Architecture, OperatingSystem, Triple}
 mod abi;
 pub(crate) mod inst;
 mod lower;
-mod lower_inst;
 mod settings;
 
 use inst::create_reg_env;
@@ -267,11 +266,11 @@ mod test {
         // on it to update:
         // > aarch64-linux-gnu-objdump -b binary -D <file> -m aarch64
         //
-        // 0:   d2824682        mov     x2, #0x1234                     // #4660
+        // 0:   52824682        mov     w2, #0x1234                     // #4660
         // 4:   0b020000        add     w0, w0, w2
         // 8:   d65f03c0        ret
 
-        let golden = vec![130, 70, 130, 210, 0, 0, 2, 11, 192, 3, 95, 214];
+        let golden = vec![130, 70, 130, 82, 0, 0, 2, 11, 192, 3, 95, 214];
 
         assert_eq!(code, &golden[..]);
     }
@@ -325,24 +324,24 @@ mod test {
         // on it to update:
         // > aarch64-linux-gnu-objdump -b binary -D <file> -m aarch64
         //
-        //   0:   d2824689        mov     x9, #0x1234                     // #4660
+        //   0:   52824689        mov     w9, #0x1234                     // #4660
         //   4:   0b09000b        add     w11, w0, w9
         //   8:   2a0b03ea        mov     w10, w11
         //   c:   b50000aa        cbnz    x10, 0x20
-        //  10:   d282468c        mov     x12, #0x1234                    // #4660
+        //  10:   5282468c        mov     w12, #0x1234                    // #4660
         //  14:   0b0c016e        add     w14, w11, w12
         //  18:   2a0e03ed        mov     w13, w14
         //  1c:   b5ffffad        cbnz    x13, 0x10
         //  20:   2a0b03e0        mov     w0, w11
         //  24:   b5ffff60        cbnz    x0, 0x10
-        //  28:   d2824681        mov     x1, #0x1234                     // #4660
+        //  28:   52824681        mov     w1, #0x1234                     // #4660
         //  2c:   4b010160        sub     w0, w11, w1
         //  30:   d65f03c0        ret
 
         let golden = vec![
-            137, 70, 130, 210, 11, 0, 9, 11, 234, 3, 11, 42, 170, 0, 0, 181, 140, 70, 130, 210,
+            137, 70, 130, 82, 11, 0, 9, 11, 234, 3, 11, 42, 170, 0, 0, 181, 140, 70, 130, 82, 110,
-            110, 1, 12, 11, 237, 3, 14, 42, 173, 255, 255, 181, 224, 3, 11, 42, 96, 255, 255, 181,
+            1, 12, 11, 237, 3, 14, 42, 173, 255, 255, 181, 224, 3, 11, 42, 96, 255, 255, 181, 129,
-            129, 70, 130, 210, 96, 1, 1, 75, 192, 3, 95, 214,
+            70, 130, 82, 96, 1, 1, 75, 192, 3, 95, 214,
         ];
 
         assert_eq!(code, &golden[..]);
@@ -412,18 +411,17 @@ mod test {
         //  1c:   d61f00e0        br      x7
         //  20:   00000010        udf     #16
         //  24:   00000018        udf     #24
-        //  28:   d2800060        mov     x0, #0x3                        // #3
+        //  28:   52800060        mov     w0, #0x3                        // #3
         //  2c:   d65f03c0        ret
-        //  30:   d2800020        mov     x0, #0x1                        // #1
+        //  30:   52800020        mov     w0, #0x1                        // #1
         //  34:   d65f03c0        ret
-        //  38:   d2800040        mov     x0, #0x2                        // #2
+        //  38:   52800040        mov     w0, #0x2                        // #2
         //  3c:   d65f03c0        ret
 
         let golden = vec![
             31, 8, 0, 113, 34, 1, 0, 84, 232, 35, 128, 154, 159, 34, 3, 213, 135, 0, 0, 16, 232,
             88, 168, 184, 231, 0, 8, 139, 224, 0, 31, 214, 16, 0, 0, 0, 24, 0, 0, 0, 96, 0, 128,
-            210, 192, 3, 95, 214, 32, 0, 128, 210, 192, 3, 95, 214, 64, 0, 128, 210, 192, 3, 95,
+            82, 192, 3, 95, 214, 32, 0, 128, 82, 192, 3, 95, 214, 64, 0, 128, 82, 192, 3, 95, 214,
-            214,
         ];
 
         assert_eq!(code, &golden[..]);

cranelift/codegen/src/isa/riscv64/inst/mod.rs

@@ -720,44 +720,6 @@ impl MachInst for Inst {
         x
     }
 
-    fn gen_constant<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        ty: Type,
-        mut alloc_tmp: F,
-    ) -> SmallVec<[Inst; 4]> {
-        if (ty.bits() <= 64 && ty.is_int()) || ty == R32 || ty == R64 {
-            return Inst::load_constant_u64(
-                to_regs.only_reg().unwrap(),
-                value as u64,
-                &mut alloc_tmp,
-            );
-        };
-        match ty {
-            F32 => {
-                Inst::load_fp_constant32(to_regs.only_reg().unwrap(), value as u32, &mut alloc_tmp)
-            }
-            F64 => {
-                Inst::load_fp_constant64(to_regs.only_reg().unwrap(), value as u64, &mut alloc_tmp)
-            }
-            I128 => {
-                let mut insts = SmallInstVec::new();
-                insts.extend(Inst::load_constant_u64(
-                    to_regs.regs()[0],
-                    (value >> 64) as u64,
-                    &mut alloc_tmp,
-                ));
-                insts.extend(Inst::load_constant_u64(
-                    to_regs.regs()[1],
-                    value as u64,
-                    &mut alloc_tmp,
-                ));
-                return insts;
-            }
-            _ => unreachable!("vector type not implemented now."),
-        }
-    }
-
     fn gen_nop(preferred_size: usize) -> Inst {
         if preferred_size == 0 {
             return Inst::Nop0;

cranelift/codegen/src/isa/riscv64/lower.isle

@@ -9,6 +9,16 @@
 (rule (lower (has_type ty (iconst (u64_from_imm64 n))))
   (imm ty n))
 
+;;;; Rules for `f32const` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(rule (lower (f32const (u64_from_ieee32 n)))
+  (imm $F32 n))
+
+;;;; Rules for `f64const` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(rule (lower (f64const (u64_from_ieee64 n)))
+  (imm $F64 n))
+
 ;;;; Rules for `null` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (rule (lower (has_type ty (null)))

cranelift/codegen/src/isa/riscv64/lower.rs

@@ -1,5 +1,4 @@
 //! Lowering rules for Riscv64.
-use super::lower_inst;
 use crate::ir::Inst as IRInst;
 use crate::isa::riscv64::inst::*;
 use crate::isa::riscv64::Riscv64Backend;
@@ -14,8 +13,22 @@ pub mod isle;
 impl LowerBackend for Riscv64Backend {
     type MInst = Inst;
 
-    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<()> {
+    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<InstOutput> {
-        lower_inst::lower_insn_to_regs(ctx, ir_inst, &self.triple, &self.flags, &self.isa_flags)
+        if let Some(temp_regs) = super::lower::isle::lower(ctx, self, ir_inst) {
+            return Ok(temp_regs);
+        }
+
+        let ty = if ctx.num_outputs(ir_inst) > 0 {
+            Some(ctx.output_ty(ir_inst, 0))
+        } else {
+            None
+        };
+
+        unreachable!(
+            "not implemented in ISLE: inst = `{}`, type = `{:?}`",
+            ctx.dfg().display_inst(ir_inst),
+            ty
+        );
     }
 
     fn lower_branch_group(
@@ -38,14 +51,8 @@ impl LowerBackend for Riscv64Backend {
 
         // Lower the first branch in ISLE.  This will automatically handle
         // the second branch (if any) by emitting a two-way conditional branch.
-        if let Ok(()) = super::lower::isle::lower_branch(
+        if let Some(temp_regs) = super::lower::isle::lower_branch(ctx, self, branches[0], targets) {
-            ctx,
+            assert!(temp_regs.len() == 0);
-            &self.triple,
-            &self.flags,
-            &self.isa_flags,
-            branches[0],
-            targets,
-        ) {
             return Ok(());
         }
         unreachable!(

cranelift/codegen/src/isa/riscv64/lower/isle.rs

@@ -8,25 +8,23 @@ use generated_code::{Context, MInst};
 // Types that the generated ISLE code uses via `use super::*`.
 use super::{writable_zero_reg, zero_reg};
 use crate::isa::riscv64::abi::Riscv64ABICaller;
-use crate::isa::riscv64::settings::Flags as IsaFlags;
+use crate::isa::riscv64::Riscv64Backend;
 use crate::machinst::Reg;
 use crate::machinst::{isle::*, MachInst, SmallInstVec};
 use crate::machinst::{VCodeConstant, VCodeConstantData};
-use crate::settings::Flags;
 use crate::{
     ir::{
         immediates::*, types::*, AtomicRmwOp, ExternalName, Inst, InstructionData, MemFlags,
         StackSlot, TrapCode, Value, ValueList,
     },
     isa::riscv64::inst::*,
-    machinst::{ArgPair, InsnOutput, Lower},
+    machinst::{ArgPair, InstOutput, Lower},
 };
 use crate::{isle_common_prelude_methods, isle_lower_prelude_methods};
 use regalloc2::PReg;
 use std::boxed::Box;
 use std::convert::TryFrom;
 use std::vec::Vec;
-use target_lexicon::Triple;
 
 type BoxCallInfo = Box<CallInfo>;
 type BoxCallIndInfo = Box<CallIndInfo>;
@@ -38,28 +36,20 @@ use crate::machinst::valueregs;
 /// The main entry point for lowering with ISLE.
 pub(crate) fn lower(
     lower_ctx: &mut Lower<MInst>,
-    flags: &Flags,
+    backend: &Riscv64Backend,
-    triple: &Triple,
-    isa_flags: &IsaFlags,
-    outputs: &[InsnOutput],
     inst: Inst,
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower(&mut isle_ctx, inst)
-        isa_flags,
-        outputs,
-        inst,
-        |cx, insn| generated_code::constructor_lower(cx, insn),
-    )
 }
 
-impl IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl IsleContext<'_, '_, MInst, Riscv64Backend> {
     isle_prelude_method_helpers!(Riscv64ABICaller);
 }
 
-impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl generated_code::Context for IsleContext<'_, '_, MInst, Riscv64Backend> {
     isle_lower_prelude_methods!();
     isle_prelude_caller_methods!(Riscv64MachineDeps, Riscv64ABICaller);
 
@@ -134,7 +124,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
         InstOutput::default()
     }
     fn load_ra(&mut self) -> Reg {
-        if self.flags.preserve_frame_pointers() {
+        if self.backend.flags.preserve_frame_pointers() {
             let tmp = self.temp_writable_reg(I64);
             self.emit(&MInst::Load {
                 rd: tmp,
@@ -198,8 +188,13 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     fn imm(&mut self, ty: Type, val: u64) -> Reg {
         let tmp = self.temp_writable_reg(ty);
-        let insts = &MInst::load_constant_u64(tmp, val, &mut |ty| self.temp_writable_reg(ty));
+        let alloc_tmp = &mut |ty| self.temp_writable_reg(ty);
-        self.emit_list(insts);
+        let insts = match ty {
+            F32 => MInst::load_fp_constant32(tmp, val as u32, alloc_tmp),
+            F64 => MInst::load_fp_constant64(tmp, val, alloc_tmp),
+            _ => MInst::load_constant_u64(tmp, val, alloc_tmp),
+        };
+        self.emit_list(&insts);
         tmp.to_reg()
     }
     #[inline]
@@ -309,10 +304,10 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
     }
 
     fn has_b(&mut self) -> bool {
-        self.isa_flags.has_b()
+        self.backend.isa_flags.has_b()
     }
     fn has_zbkb(&mut self) -> bool {
-        self.isa_flags.has_zbkb()
+        self.backend.isa_flags.has_zbkb()
     }
 
     fn inst_output_get(&mut self, x: InstOutput, index: u8) -> ValueRegs {
@@ -436,7 +431,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
     }
 }
 
-impl IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl IsleContext<'_, '_, MInst, Riscv64Backend> {
     #[inline]
     fn emit_list(&mut self, list: &SmallInstVec<MInst>) {
         for i in list {
@@ -448,21 +443,14 @@ impl IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
 /// The main entry point for branch lowering with ISLE.
 pub(crate) fn lower_branch(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &Riscv64Backend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
     branch: Inst,
     targets: &[MachLabel],
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower_branch(&mut isle_ctx, branch, &targets.to_vec())
-        isa_flags,
-        &[],
-        branch,
-        |cx, insn| generated_code::constructor_lower_branch(cx, insn, &targets.to_vec()),
-    )
 }
 
 /// construct destination according to ty.

cranelift/codegen/src/isa/riscv64/lower_inst.rs

@@ -1,36 +0,0 @@
-//! Lower a single Cranelift instruction into vcode.
-
-use crate::ir::Inst as IRInst;
-
-use crate::isa::riscv64::settings as riscv64_settings;
-use crate::machinst::lower::*;
-use crate::machinst::*;
-use crate::settings::Flags;
-use crate::CodegenResult;
-
-use crate::isa::riscv64::inst::*;
-use target_lexicon::Triple;
-
-/// Actually codegen an instruction's results into registers.
-pub(crate) fn lower_insn_to_regs(
-    ctx: &mut Lower<Inst>,
-    insn: IRInst,
-    triple: &Triple,
-    flags: &Flags,
-    isa_flags: &riscv64_settings::Flags,
-) -> CodegenResult<()> {
-    let outputs = insn_outputs(ctx, insn);
-    let ty = if outputs.len() > 0 {
-        Some(ctx.output_ty(insn, 0))
-    } else {
-        None
-    };
-    if let Ok(()) = super::lower::isle::lower(ctx, flags, triple, isa_flags, &outputs, insn) {
-        return Ok(());
-    }
-    unreachable!(
-        "not implemented in ISLE: inst = `{}`, type = `{:?}`",
-        ctx.dfg().display_inst(insn),
-        ty
-    );
-}

cranelift/codegen/src/isa/riscv64/mod.rs

@@ -19,7 +19,6 @@ use target_lexicon::{Architecture, Triple};
 mod abi;
 pub(crate) mod inst;
 mod lower;
-mod lower_inst;
 mod settings;
 #[cfg(feature = "unwind")]
 use crate::isa::unwind::systemv;

cranelift/codegen/src/isa/s390x/inst.isle

@@ -2983,49 +2983,49 @@
 (decl imm (Type u64) Reg)
 
 ;; 16-bit (or smaller) result type, any value
-(rule 5 (imm (fits_in_16 ty) n)
+(rule 7 (imm (fits_in_16 ty) n)
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov32SImm16 dst (u64_as_i16 n)))))
         dst))
 
 ;; 32-bit result type, value fits in i16
-(rule 4 (imm (gpr32_ty ty) (i16_from_u64 n))
+(rule 6 (imm (gpr32_ty ty) (i16_from_u64 n))
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov32SImm16 dst n))))
         dst))
 
 ;; 32-bit result type, any value
-(rule 3 (imm (gpr32_ty ty) n)
+(rule 5 (imm (gpr32_ty ty) n)
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov32Imm dst (u64_as_u32 n)))))
         dst))
 
 ;; 64-bit result type, value fits in i16
-(rule 6 (imm (gpr64_ty ty) (i16_from_u64 n))
+(rule 4 (imm (gpr64_ty ty) (i16_from_u64 n))
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov64SImm16 dst n))))
         dst))
 
 ;; 64-bit result type, value fits in i32
-(rule 2 (imm (gpr64_ty ty) (i32_from_u64 n))
+(rule 3 (imm (gpr64_ty ty) (i32_from_u64 n))
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov64SImm32 dst n))))
         dst))
 
 ;; 64-bit result type, value fits in UImm16Shifted
-(rule 1 (imm (gpr64_ty ty) (uimm16shifted_from_u64 n))
+(rule 2 (imm (gpr64_ty ty) (uimm16shifted_from_u64 n))
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov64UImm16Shifted dst n))))
         dst))
 
 ;; 64-bit result type, value fits in UImm32Shifted
-(rule 0 (imm (gpr64_ty ty) (uimm32shifted_from_u64 n))
+(rule 1 (imm (gpr64_ty ty) (uimm32shifted_from_u64 n))
       (let ((dst WritableReg (temp_writable_reg ty))
             (_ Unit (emit (MInst.Mov64UImm32Shifted dst n))))
         dst))
 
 ;; 64-bit result type, value with non-zero low-/high-parts.
-(rule 7 (imm (gpr64_ty ty) (and (u64_nonzero_hipart hi)
+(rule 0 (imm (gpr64_ty ty) (and (u64_nonzero_hipart hi)
                                 (u64_nonzero_lopart lo)))
       (insert_imm ty (imm ty hi) lo))
 

cranelift/codegen/src/isa/s390x/inst/emit.rs

@@ -104,7 +104,15 @@ pub fn mem_finalize(
             } else {
                 let tmp = writable_spilltmp_reg();
                 assert!(base != tmp.to_reg());
-                insts.extend(Inst::load_constant64(tmp, off as u64, |_| tmp));
+                if let Ok(imm) = i16::try_from(off) {
+                    insts.push(Inst::Mov64SImm16 { rd: tmp, imm });
+                } else if let Ok(imm) = i32::try_from(off) {
+                    insts.push(Inst::Mov64SImm32 { rd: tmp, imm });
+                } else {
+                    // The offset must be smaller than the stack frame size,
+                    // which the ABI code limits to 128 MB.
+                    unreachable!();
+                }
                 MemArg::reg_plus_reg(base, tmp.to_reg(), mem.get_flags())
             }
         }

cranelift/codegen/src/isa/s390x/inst/emit_tests.rs

@@ -3,6 +3,7 @@ use crate::isa::s390x::inst::*;
 use crate::isa::s390x::settings as s390x_settings;
 use crate::settings;
 use alloc::vec::Vec;
+use smallvec::smallvec;
 
 #[cfg(test)]
 fn simm20_zero() -> SImm20 {
@@ -6366,30 +6367,6 @@ fn test_s390x_binemit() {
         "C0117FFFFFFF41112000",
         "lgfi %r1, 2147483647 ; la %r1, 0(%r1,%r2)",
     ));
-    insns.push((
-        Inst::LoadAddr {
-            rd: writable_gpr(1),
-            mem: MemArg::RegOffset {
-                reg: gpr(2),
-                off: -9223372036854775808,
-                flags: MemFlags::trusted(),
-            },
-        },
-        "A51C800041112000",
-        "llihh %r1, 32768 ; la %r1, 0(%r1,%r2)",
-    ));
-    insns.push((
-        Inst::LoadAddr {
-            rd: writable_gpr(1),
-            mem: MemArg::RegOffset {
-                reg: gpr(2),
-                off: 9223372036854775807,
-                flags: MemFlags::trusted(),
-            },
-        },
-        "C01E7FFFFFFFC019FFFFFFFF41112000",
-        "llihf %r1, 2147483647 ; iilf %r1, 4294967295 ; la %r1, 0(%r1,%r2)",
-    ));
 
     insns.push((
         Inst::Mov64 {

cranelift/codegen/src/isa/s390x/inst/mod.rs

@@ -8,9 +8,8 @@ use crate::machinst::*;
 use crate::{settings, CodegenError, CodegenResult};
 use alloc::boxed::Box;
 use alloc::vec::Vec;
-use core::convert::TryFrom;
 use regalloc2::{PRegSet, VReg};
-use smallvec::{smallvec, SmallVec};
+use smallvec::SmallVec;
 use std::string::{String, ToString};
 pub mod regs;
 pub use self::regs::*;
@@ -334,102 +333,6 @@ impl Inst {
         }
     }
 
-    /// Create an instruction that loads a 64-bit integer constant.
-    pub fn load_constant64<F: FnMut(Type) -> Writable<Reg>>(
-        rd: Writable<Reg>,
-        value: u64,
-        mut alloc_tmp: F,
-    ) -> SmallVec<[Inst; 4]> {
-        if let Ok(imm) = i16::try_from(value as i64) {
-            // 16-bit signed immediate
-            smallvec![Inst::Mov64SImm16 { rd, imm }]
-        } else if let Ok(imm) = i32::try_from(value as i64) {
-            // 32-bit signed immediate
-            smallvec![Inst::Mov64SImm32 { rd, imm }]
-        } else if let Some(imm) = UImm16Shifted::maybe_from_u64(value) {
-            // 16-bit shifted immediate
-            smallvec![Inst::Mov64UImm16Shifted { rd, imm }]
-        } else if let Some(imm) = UImm32Shifted::maybe_from_u64(value) {
-            // 32-bit shifted immediate
-            smallvec![Inst::Mov64UImm32Shifted { rd, imm }]
-        } else {
-            let mut insts = smallvec![];
-            let hi = value & 0xffff_ffff_0000_0000u64;
-            let lo = value & 0x0000_0000_ffff_ffffu64;
-
-            let hi_rd = alloc_tmp(types::I64);
-            if let Some(imm) = UImm16Shifted::maybe_from_u64(hi) {
-                // 16-bit shifted immediate
-                insts.push(Inst::Mov64UImm16Shifted { rd: hi_rd, imm });
-            } else if let Some(imm) = UImm32Shifted::maybe_from_u64(hi) {
-                // 32-bit shifted immediate
-                insts.push(Inst::Mov64UImm32Shifted { rd: hi_rd, imm });
-            } else {
-                unreachable!();
-            }
-
-            if let Some(imm) = UImm16Shifted::maybe_from_u64(lo) {
-                // 16-bit shifted immediate
-                insts.push(Inst::Insert64UImm16Shifted {
-                    rd,
-                    ri: hi_rd.to_reg(),
-                    imm,
-                });
-            } else if let Some(imm) = UImm32Shifted::maybe_from_u64(lo) {
-                // 32-bit shifted immediate
-                insts.push(Inst::Insert64UImm32Shifted {
-                    rd,
-                    ri: hi_rd.to_reg(),
-                    imm,
-                });
-            } else {
-                unreachable!();
-            }
-
-            insts
-        }
-    }
-
-    /// Create an instruction that loads a 32-bit integer constant.
-    pub fn load_constant32(rd: Writable<Reg>, value: u32) -> SmallVec<[Inst; 4]> {
-        if let Ok(imm) = i16::try_from(value as i32) {
-            // 16-bit signed immediate
-            smallvec![Inst::Mov32SImm16 { rd, imm }]
-        } else {
-            // 32-bit full immediate
-            smallvec![Inst::Mov32Imm { rd, imm: value }]
-        }
-    }
-
-    /// Create an instruction that loads a 32-bit floating-point constant.
-    pub fn load_fp_constant32(rd: Writable<Reg>, value: f32) -> Inst {
-        // TODO: use LZER to load 0.0
-        Inst::LoadFpuConst32 {
-            rd,
-            const_data: value.to_bits(),
-        }
-    }
-
-    /// Create an instruction that loads a 64-bit floating-point constant.
-    pub fn load_fp_constant64(rd: Writable<Reg>, value: f64) -> Inst {
-        // TODO: use LZDR to load 0.0
-        Inst::LoadFpuConst64 {
-            rd,
-            const_data: value.to_bits(),
-        }
-    }
-
-    /// Create an instruction that loads a 128-bit floating-point constant.
-    pub fn load_vec_constant(rd: Writable<Reg>, value: u128) -> Inst {
-        // FIXME: This doesn't special-case constants that can be loaded
-        // without a constant pool, like the ISLE lowering does.  Ideally,
-        // we should not have to duplicate the logic here.
-        Inst::VecLoadConst {
-            rd,
-            const_data: value,
-        }
-    }
-
     /// Generic constructor for a load (zero-extending where appropriate).
     pub fn gen_load(into_reg: Writable<Reg>, mem: MemArg, ty: Type) -> Inst {
         match ty {
@@ -1180,48 +1083,6 @@ impl MachInst for Inst {
         }
     }
 
-    fn gen_constant<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        ty: Type,
-        alloc_tmp: F,
-    ) -> SmallVec<[Inst; 4]> {
-        let to_reg = to_regs
-            .only_reg()
-            .expect("multi-reg values not supported yet");
-        match ty {
-            types::I128 => {
-                let mut ret = SmallVec::new();
-                ret.push(Inst::load_vec_constant(to_reg, value));
-                ret
-            }
-            _ if ty.is_vector() && ty.bits() == 128 => {
-                let mut ret = SmallVec::new();
-                ret.push(Inst::load_vec_constant(to_reg, value));
-                ret
-            }
-            types::F64 => {
-                let mut ret = SmallVec::new();
-                ret.push(Inst::load_fp_constant64(
-                    to_reg,
-                    f64::from_bits(value as u64),
-                ));
-                ret
-            }
-            types::F32 => {
-                let mut ret = SmallVec::new();
-                ret.push(Inst::load_fp_constant32(
-                    to_reg,
-                    f32::from_bits(value as u32),
-                ));
-                ret
-            }
-            types::I64 | types::R64 => Inst::load_constant64(to_reg, value as u64, alloc_tmp),
-            types::I8 | types::I16 | types::I32 => Inst::load_constant32(to_reg, value as u32),
-            _ => unreachable!(),
-        }
-    }
-
     fn gen_nop(preferred_size: usize) -> Inst {
         if preferred_size == 0 {
             Inst::Nop0

cranelift/codegen/src/isa/s390x/lower.rs

@@ -4,9 +4,8 @@ use crate::ir::Inst as IRInst;
 use crate::ir::Opcode;
 use crate::isa::s390x::inst::Inst;
 use crate::isa::s390x::S390xBackend;
-use crate::machinst::{InsnOutput, Lower, LowerBackend, MachLabel};
+use crate::machinst::{InstOutput, Lower, LowerBackend, MachLabel};
 use crate::CodegenResult;
-use smallvec::SmallVec;
 
 pub mod isle;
 
@@ -16,31 +15,18 @@ pub mod isle;
 impl LowerBackend for S390xBackend {
     type MInst = Inst;
 
-    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<()> {
+    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<InstOutput> {
+        if let Some(temp_regs) = super::lower::isle::lower(ctx, self, ir_inst) {
+            return Ok(temp_regs);
+        }
+
         let op = ctx.data(ir_inst).opcode();
-        let outputs: SmallVec<[InsnOutput; 2]> = (0..ctx.num_outputs(ir_inst))
+        let ty = if ctx.num_outputs(ir_inst) > 0 {
-            .map(|i| InsnOutput {
-                insn: ir_inst,
-                output: i,
-            })
-            .collect();
-        let ty = if outputs.len() > 0 {
             Some(ctx.output_ty(ir_inst, 0))
         } else {
             None
         };
 
-        if let Ok(()) = super::lower::isle::lower(
-            ctx,
-            &self.triple,
-            &self.flags,
-            &self.isa_flags,
-            &outputs,
-            ir_inst,
-        ) {
-            return Ok(());
-        }
-
         match op {
             Opcode::Nop
             | Opcode::Iconst
@@ -271,14 +257,8 @@ impl LowerBackend for S390xBackend {
 
         // Lower the first branch in ISLE.  This will automatically handle
         // the second branch (if any) by emitting a two-way conditional branch.
-        if let Ok(()) = super::lower::isle::lower_branch(
+        if let Some(temp_regs) = super::lower::isle::lower_branch(ctx, self, branches[0], targets) {
-            ctx,
+            assert!(temp_regs.len() == 0);
-            &self.triple,
-            &self.flags,
-            &self.isa_flags,
-            branches[0],
-            targets,
-        ) {
             return Ok(());
         }
         unreachable!(

cranelift/codegen/src/isa/s390x/lower/isle.rs

@@ -11,10 +11,9 @@ use crate::isa::s390x::inst::{
     MemArg, MemArgPair, RegPair, SymbolReloc, UImm12, UImm16Shifted, UImm32Shifted,
     WritableRegPair,
 };
-use crate::isa::s390x::settings::Flags as IsaFlags;
+use crate::isa::s390x::S390xBackend;
 use crate::machinst::isle::*;
 use crate::machinst::{MachLabel, Reg};
-use crate::settings::Flags;
 use crate::{
     ir::{
         condcodes::*, immediates::*, types::*, ArgumentPurpose, AtomicRmwOp, Endianness, Inst,
@@ -24,7 +23,7 @@ use crate::{
     isa::CallConv,
     machinst::abi::ABIMachineSpec,
     machinst::{
-        ArgPair, CallArgList, CallArgPair, CallRetList, CallRetPair, InsnOutput, Lower, MachInst,
+        ArgPair, CallArgList, CallArgPair, CallRetList, CallRetPair, InstOutput, Lower, MachInst,
         VCodeConstant, VCodeConstantData,
     },
 };
@@ -35,7 +34,6 @@ use std::boxed::Box;
 use std::cell::Cell;
 use std::convert::TryFrom;
 use std::vec::Vec;
-use target_lexicon::Triple;
 
 /// Information describing a library call to be emitted.
 pub struct LibCallInfo {
@@ -58,44 +56,29 @@ type CallArgListBuilder = Cell<CallArgList>;
 /// The main entry point for lowering with ISLE.
 pub(crate) fn lower(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &S390xBackend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
-    outputs: &[InsnOutput],
     inst: Inst,
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower(&mut isle_ctx, inst)
-        isa_flags,
-        outputs,
-        inst,
-        |cx, insn| generated_code::constructor_lower(cx, insn),
-    )
 }
 
 /// The main entry point for branch lowering with ISLE.
 pub(crate) fn lower_branch(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &S390xBackend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
     branch: Inst,
     targets: &[MachLabel],
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower_branch(&mut isle_ctx, branch, &targets.to_vec())
-        isa_flags,
-        &[],
-        branch,
-        |cx, insn| generated_code::constructor_lower_branch(cx, insn, &targets.to_vec()),
-    )
 }
 
-impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl generated_code::Context for IsleContext<'_, '_, MInst, S390xBackend> {
     isle_lower_prelude_methods!();
 
     #[inline]
@@ -283,7 +266,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     fn lib_call_info(&mut self, info: &LibCallInfo) -> BoxCallInfo {
         let caller_callconv = self.lower_ctx.abi().call_conv(self.lower_ctx.sigs());
-        let callee_callconv = CallConv::for_libcall(&self.flags, caller_callconv);
+        let callee_callconv = CallConv::for_libcall(&self.backend.flags, caller_callconv);
 
         // Clobbers are defined by the calling convention.  Remove defs from clobbers.
         let mut clobbers = S390xMachineDeps::get_regs_clobbered_by_call(callee_callconv);
@@ -310,7 +293,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     #[inline]
     fn allow_div_traps(&mut self, _: Type) -> Option<()> {
-        if !self.flags.avoid_div_traps() {
+        if !self.backend.flags.avoid_div_traps() {
             Some(())
         } else {
             None
@@ -319,7 +302,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     #[inline]
     fn mie2_enabled(&mut self, _: Type) -> Option<()> {
-        if self.isa_flags.has_mie2() {
+        if self.backend.isa_flags.has_mie2() {
             Some(())
         } else {
             None
@@ -328,7 +311,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     #[inline]
     fn mie2_disabled(&mut self, _: Type) -> Option<()> {
-        if !self.isa_flags.has_mie2() {
+        if !self.backend.isa_flags.has_mie2() {
             Some(())
         } else {
             None
@@ -337,7 +320,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     #[inline]
     fn vxrs_ext2_enabled(&mut self, _: Type) -> Option<()> {
-        if self.isa_flags.has_vxrs_ext2() {
+        if self.backend.isa_flags.has_vxrs_ext2() {
             Some(())
         } else {
             None
@@ -346,7 +329,7 @@ impl generated_code::Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6>
 
     #[inline]
     fn vxrs_ext2_disabled(&mut self, _: Type) -> Option<()> {
-        if !self.isa_flags.has_vxrs_ext2() {
+        if !self.backend.isa_flags.has_vxrs_ext2() {
             Some(())
         } else {
             None

cranelift/codegen/src/isa/x64/abi.rs

@@ -637,12 +637,7 @@ impl ABIMachineSpec for X64ABIMachineSpec {
         let arg2 = get_intreg_for_arg(&call_conv, 2, 2).unwrap();
         let temp = alloc_tmp(Self::word_type());
         let temp2 = alloc_tmp(Self::word_type());
-        insts.extend(
+        insts.push(Inst::imm(OperandSize::Size64, size as u64, temp));
-            Inst::gen_constant(ValueRegs::one(temp), size as u128, I64, |_| {
-                panic!("tmp should not be needed")
-            })
-            .into_iter(),
-        );
         // We use an indirect call and a full LoadExtName because we do not have
         // information about the libcall `RelocDistance` here, so we
         // conservatively use the more flexible calling sequence.

cranelift/codegen/src/isa/x64/inst/mod.rs

@@ -2336,110 +2336,6 @@ impl MachInst for Inst {
         Inst::jmp_known(label)
     }
 
-    fn gen_constant<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        ty: Type,
-        mut alloc_tmp: F,
-    ) -> SmallVec<[Self; 4]> {
-        let mut ret = SmallVec::new();
-        if ty == types::I128 {
-            let lo = value as u64;
-            let hi = (value >> 64) as u64;
-            let lo_reg = to_regs.regs()[0];
-            let hi_reg = to_regs.regs()[1];
-            if lo == 0 {
-                ret.push(Inst::alu_rmi_r(
-                    OperandSize::Size64,
-                    AluRmiROpcode::Xor,
-                    RegMemImm::reg(lo_reg.to_reg()),
-                    lo_reg,
-                ));
-            } else {
-                ret.push(Inst::imm(OperandSize::Size64, lo, lo_reg));
-            }
-            if hi == 0 {
-                ret.push(Inst::alu_rmi_r(
-                    OperandSize::Size64,
-                    AluRmiROpcode::Xor,
-                    RegMemImm::reg(hi_reg.to_reg()),
-                    hi_reg,
-                ));
-            } else {
-                ret.push(Inst::imm(OperandSize::Size64, hi, hi_reg));
-            }
-        } else {
-            let to_reg = to_regs
-                .only_reg()
-                .expect("multi-reg values not supported on x64");
-            if ty == types::F32 {
-                if value == 0 {
-                    ret.push(Inst::xmm_rm_r(
-                        SseOpcode::Xorps,
-                        RegMem::reg(to_reg.to_reg()),
-                        to_reg,
-                    ));
-                } else {
-                    let tmp = alloc_tmp(types::I32);
-                    ret.push(Inst::imm(OperandSize::Size32, value as u64, tmp));
-
-                    ret.push(Inst::gpr_to_xmm(
-                        SseOpcode::Movd,
-                        RegMem::reg(tmp.to_reg()),
-                        OperandSize::Size32,
-                        to_reg,
-                    ));
-                }
-            } else if ty == types::F64 {
-                if value == 0 {
-                    ret.push(Inst::xmm_rm_r(
-                        SseOpcode::Xorpd,
-                        RegMem::reg(to_reg.to_reg()),
-                        to_reg,
-                    ));
-                } else {
-                    let tmp = alloc_tmp(types::I64);
-                    ret.push(Inst::imm(OperandSize::Size64, value as u64, tmp));
-
-                    ret.push(Inst::gpr_to_xmm(
-                        SseOpcode::Movq,
-                        RegMem::reg(tmp.to_reg()),
-                        OperandSize::Size64,
-                        to_reg,
-                    ));
-                }
-            } else {
-                // Must be an integer type.
-                debug_assert!(
-                    ty == types::I8
-                        || ty == types::I16
-                        || ty == types::I32
-                        || ty == types::I64
-                        || ty == types::R32
-                        || ty == types::R64
-                );
-                // Immediates must be 32 or 64 bits.
-                // Smaller types are widened.
-                let size = match OperandSize::from_ty(ty) {
-                    OperandSize::Size64 => OperandSize::Size64,
-                    _ => OperandSize::Size32,
-                };
-                if value == 0 {
-                    ret.push(Inst::alu_rmi_r(
-                        size,
-                        AluRmiROpcode::Xor,
-                        RegMemImm::reg(to_reg.to_reg()),
-                        to_reg,
-                    ));
-                } else {
-                    let value = value as u64;
-                    ret.push(Inst::imm(size, value.into(), to_reg));
-                }
-            }
-        }
-        ret
-    }
-
     fn gen_dummy_use(reg: Reg) -> Self {
         Inst::DummyUse { reg }
     }

cranelift/codegen/src/isa/x64/lower.rs

@@ -7,13 +7,13 @@ use crate::ir::{types, ExternalName, Inst as IRInst, LibCall, Opcode, Type};
 use crate::isa::x64::abi::*;
 use crate::isa::x64::inst::args::*;
 use crate::isa::x64::inst::*;
-use crate::isa::{x64::settings as x64_settings, x64::X64Backend, CallConv};
+use crate::isa::{x64::X64Backend, CallConv};
 use crate::machinst::abi::SmallInstVec;
 use crate::machinst::lower::*;
 use crate::machinst::*;
 use crate::result::CodegenResult;
 use crate::settings::Flags;
-use smallvec::{smallvec, SmallVec};
+use smallvec::smallvec;
 use target_lexicon::Triple;
 
 //=============================================================================
@@ -41,27 +41,6 @@ fn matches_input(ctx: &mut Lower<Inst>, input: InsnInput, op: Opcode) -> Option<
     })
 }
 
-/// Emits instruction(s) to generate the given 64-bit constant value into a newly-allocated
-/// temporary register, returning that register.
-fn generate_constant(ctx: &mut Lower<Inst>, ty: Type, c: u64) -> ValueRegs<Reg> {
-    let from_bits = ty_bits(ty);
-    let masked = if from_bits < 64 {
-        c & ((1u64 << from_bits) - 1)
-    } else {
-        c
-    };
-
-    let cst_copy = ctx.alloc_tmp(ty);
-    for inst in Inst::gen_constant(cst_copy, masked as u128, ty, |ty| {
-        ctx.alloc_tmp(ty).only_reg().unwrap()
-    })
-    .into_iter()
-    {
-        ctx.emit(inst);
-    }
-    non_writable_value_regs(cst_copy)
-}
-
 /// Put the given input into possibly multiple registers, and mark it as used (side-effect).
 fn put_input_in_regs(ctx: &mut Lower<Inst>, spec: InsnInput) -> ValueRegs<Reg> {
     let ty = ctx.input_ty(spec.insn, spec.input);
@@ -69,7 +48,16 @@ fn put_input_in_regs(ctx: &mut Lower<Inst>, spec: InsnInput) -> ValueRegs<Reg> {
 
     if let Some(c) = input.constant {
         // Generate constants fresh at each use to minimize long-range register pressure.
-        generate_constant(ctx, ty, c)
+        let from_bits = ty_bits(ty);
+        let (size, c) = if from_bits < 64 {
+            (OperandSize::Size32, c & ((1u64 << from_bits) - 1))
+        } else {
+            (OperandSize::Size64, c)
+        };
+        assert!(is_int_or_ref_ty(ty)); // Only used for addresses.
+        let cst_copy = ctx.alloc_tmp(ty);
+        ctx.emit(Inst::imm(size, c, cst_copy.only_reg().unwrap()));
+        non_writable_value_regs(cst_copy)
     } else {
         ctx.put_input_in_regs(spec.insn, spec.input)
     }
@@ -306,25 +294,23 @@ fn lower_to_amode(ctx: &mut Lower<Inst>, spec: InsnInput, offset: i32) -> Amode
 }
 
 //=============================================================================
-// Top-level instruction lowering entry point, for one instruction.
+// Lowering-backend trait implementation.
 
-/// Actually codegen an instruction's results into registers.
+impl LowerBackend for X64Backend {
-fn lower_insn_to_regs(
+    type MInst = Inst;
-    ctx: &mut Lower<Inst>,
-    insn: IRInst,
-    flags: &Flags,
-    isa_flags: &x64_settings::Flags,
-    triple: &Triple,
-) -> CodegenResult<()> {
-    let outputs: SmallVec<[InsnOutput; 2]> = (0..ctx.num_outputs(insn))
-        .map(|i| InsnOutput { insn, output: i })
-        .collect();
 
-    if let Ok(()) = isle::lower(ctx, triple, flags, isa_flags, &outputs, insn) {
+    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<InstOutput> {
-        return Ok(());
+        if let Some(temp_regs) = isle::lower(ctx, self, ir_inst) {
+            return Ok(temp_regs);
         }
 
-    let op = ctx.data(insn).opcode();
+        let op = ctx.data(ir_inst).opcode();
+        let ty = if ctx.num_outputs(ir_inst) > 0 {
+            Some(ctx.output_ty(ir_inst, 0))
+        } else {
+            None
+        };
+
         match op {
             Opcode::Iconst
             | Opcode::F32const
@@ -468,15 +454,9 @@ fn lower_insn_to_regs(
             | Opcode::Uunarrow
             | Opcode::Nop
             | Opcode::Bmask => {
-            let ty = if outputs.len() > 0 {
-                Some(ctx.output_ty(insn, 0))
-            } else {
-                None
-            };
-
                 unreachable!(
                     "implemented in ISLE: inst = `{}`, type = `{:?}`",
-                ctx.dfg().display_inst(insn),
+                    ctx.dfg().display_inst(ir_inst),
                     ty
                 )
             }
@@ -544,23 +524,15 @@ fn lower_insn_to_regs(
             }
 
             Opcode::Trapz | Opcode::Trapnz | Opcode::ResumableTrapnz => {
-            panic!("trapz / trapnz / resumable_trapnz should have been removed by legalization!");
+                panic!(
+                    "trapz / trapnz / resumable_trapnz should have been removed by legalization!"
+                );
             }
 
             Opcode::Jump | Opcode::Brz | Opcode::Brnz | Opcode::BrTable => {
                 panic!("Branch opcode reached non-branch lowering logic!");
             }
         }
-}
-
-//=============================================================================
-// Lowering-backend trait implementation.
-
-impl LowerBackend for X64Backend {
-    type MInst = Inst;
-
-    fn lower(&self, ctx: &mut Lower<Inst>, ir_inst: IRInst) -> CodegenResult<()> {
-        lower_insn_to_regs(ctx, ir_inst, &self.flags, &self.x64_flags, &self.triple)
     }
 
     fn lower_branch_group(
@@ -581,14 +553,8 @@ impl LowerBackend for X64Backend {
             assert!(op1 == Opcode::Jump);
         }
 
-        if let Ok(()) = isle::lower_branch(
+        if let Some(temp_regs) = isle::lower_branch(ctx, self, branches[0], targets) {
-            ctx,
+            assert!(temp_regs.len() == 0);
-            &self.triple,
-            &self.flags,
-            &self.x64_flags,
-            branches[0],
-            targets,
-        ) {
             return Ok(());
         }
 

cranelift/codegen/src/isa/x64/lower/isle.rs

@@ -14,6 +14,7 @@ use generated_code::{Context, MInst, RegisterClass};
 use super::{is_int_or_ref_ty, is_mergeable_load, lower_to_amode};
 use crate::ir::LibCall;
 use crate::isa::x64::lower::emit_vm_call;
+use crate::isa::x64::X64Backend;
 use crate::{
     ir::{
         condcodes::{CondCode, FloatCC, IntCC},
@@ -22,16 +23,14 @@ use crate::{
         Inst, InstructionData, MemFlags, Opcode, TrapCode, Value, ValueList,
     },
     isa::{
-        settings::Flags,
         unwind::UnwindInst,
         x64::{
             abi::X64Caller,
             inst::{args::*, regs, CallInfo},
-            settings::Flags as IsaFlags,
         },
     },
     machinst::{
-        isle::*, valueregs, ArgPair, InsnInput, InsnOutput, Lower, MachAtomicRmwOp, MachInst,
+        isle::*, valueregs, ArgPair, InsnInput, InstOutput, Lower, MachAtomicRmwOp, MachInst,
         VCodeConstant, VCodeConstantData,
     },
 };
@@ -40,7 +39,6 @@ use regalloc2::PReg;
 use smallvec::SmallVec;
 use std::boxed::Box;
 use std::convert::TryFrom;
-use target_lexicon::Triple;
 
 type BoxCallInfo = Box<CallInfo>;
 type BoxVecMachLabel = Box<SmallVec<[MachLabel; 4]>>;
@@ -56,43 +54,28 @@ pub struct SinkableLoad {
 /// The main entry point for lowering with ISLE.
 pub(crate) fn lower(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &X64Backend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
-    outputs: &[InsnOutput],
     inst: Inst,
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower(&mut isle_ctx, inst)
-        isa_flags,
-        outputs,
-        inst,
-        |cx, insn| generated_code::constructor_lower(cx, insn),
-    )
 }
 
 pub(crate) fn lower_branch(
     lower_ctx: &mut Lower<MInst>,
-    triple: &Triple,
+    backend: &X64Backend,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
     branch: Inst,
     targets: &[MachLabel],
-) -> Result<(), ()> {
+) -> Option<InstOutput> {
-    lower_common(
+    // TODO: reuse the ISLE context across lowerings so we can reuse its
-        lower_ctx,
+    // internal heap allocations.
-        triple,
+    let mut isle_ctx = IsleContext { lower_ctx, backend };
-        flags,
+    generated_code::constructor_lower_branch(&mut isle_ctx, branch, &targets.to_vec())
-        isa_flags,
-        &[],
-        branch,
-        |cx, insn| generated_code::constructor_lower_branch(cx, insn, targets),
-    )
 }
 
-impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl Context for IsleContext<'_, '_, MInst, X64Backend> {
     isle_lower_prelude_methods!();
     isle_prelude_caller_methods!(X64ABIMachineSpec, X64Caller);
 
@@ -204,52 +187,52 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
 
     #[inline]
     fn avx512vl_enabled(&mut self, _: Type) -> bool {
-        self.isa_flags.use_avx512vl_simd()
+        self.backend.x64_flags.use_avx512vl_simd()
     }
 
     #[inline]
     fn avx512dq_enabled(&mut self, _: Type) -> bool {
-        self.isa_flags.use_avx512dq_simd()
+        self.backend.x64_flags.use_avx512dq_simd()
     }
 
     #[inline]
     fn avx512f_enabled(&mut self, _: Type) -> bool {
-        self.isa_flags.use_avx512f_simd()
+        self.backend.x64_flags.use_avx512f_simd()
     }
 
     #[inline]
     fn avx512bitalg_enabled(&mut self, _: Type) -> bool {
-        self.isa_flags.use_avx512bitalg_simd()
+        self.backend.x64_flags.use_avx512bitalg_simd()
     }
 
     #[inline]
     fn avx512vbmi_enabled(&mut self, _: Type) -> bool {
-        self.isa_flags.use_avx512vbmi_simd()
+        self.backend.x64_flags.use_avx512vbmi_simd()
     }
 
     #[inline]
     fn use_lzcnt(&mut self, _: Type) -> bool {
-        self.isa_flags.use_lzcnt()
+        self.backend.x64_flags.use_lzcnt()
     }
 
     #[inline]
     fn use_bmi1(&mut self, _: Type) -> bool {
-        self.isa_flags.use_bmi1()
+        self.backend.x64_flags.use_bmi1()
     }
 
     #[inline]
     fn use_popcnt(&mut self, _: Type) -> bool {
-        self.isa_flags.use_popcnt()
+        self.backend.x64_flags.use_popcnt()
     }
 
     #[inline]
     fn use_fma(&mut self, _: Type) -> bool {
-        self.isa_flags.use_fma()
+        self.backend.x64_flags.use_fma()
     }
 
     #[inline]
     fn use_sse41(&mut self, _: Type) -> bool {
-        self.isa_flags.use_sse41()
+        self.backend.x64_flags.use_sse41()
     }
 
     #[inline]
@@ -647,8 +630,8 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
 
         emit_vm_call(
             self.lower_ctx,
-            self.flags,
+            &self.backend.flags,
-            self.triple,
+            &self.backend.triple,
             libcall.clone(),
             &[a],
             &[output_reg],
@@ -665,8 +648,8 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
 
         emit_vm_call(
             self.lower_ctx,
-            self.flags,
+            &self.backend.flags,
-            self.triple,
+            &self.backend.triple,
             libcall.clone(),
             &[a, b, c],
             &[output_reg],
@@ -884,7 +867,7 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
         let dst_remainder = self.lower_ctx.alloc_tmp(types::I64).only_reg().unwrap();
 
         // Always do explicit checks for `srem`: otherwise, INT_MIN % -1 is not handled properly.
-        if self.flags.avoid_div_traps() || *kind == DivOrRemKind::SignedRem {
+        if self.backend.flags.avoid_div_traps() || *kind == DivOrRemKind::SignedRem {
             // A vcode meta-instruction is used to lower the inline checks, since they embed
             // pc-relative offsets that must not change, thus requiring regalloc to not
             // interfere by introducing spills and reloads.
@@ -1003,7 +986,7 @@ impl Context for IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
     }
 }
 
-impl IsleContext<'_, '_, MInst, Flags, IsaFlags, 6> {
+impl IsleContext<'_, '_, MInst, X64Backend> {
     isle_prelude_method_helpers!(X64Caller);
 }
 

cranelift/codegen/src/machinst/compile.rs

@@ -23,15 +23,7 @@ pub fn compile<B: LowerBackend + TargetIsa>(
     let block_order = BlockLoweringOrder::new(f);
 
     // Build the lowering context.
-    let lower = crate::machinst::Lower::new(
+    let lower = crate::machinst::Lower::new(f, machine_env, abi, emit_info, block_order, sigs)?;
-        f,
-        b.flags().clone(),
-        machine_env,
-        abi,
-        emit_info,
-        block_order,
-        sigs,
-    )?;
 
     // Lower the IR.
     let vcode = {

cranelift/codegen/src/machinst/helpers.rs

@@ -1,7 +1,5 @@
 //! Miscellaneous helpers for machine backends.
 
-use super::{InsnOutput, Lower, VCodeInst, ValueRegs};
-use super::{Reg, Writable};
 use crate::ir::Type;
 use std::ops::{Add, BitAnd, Not, Sub};
 
@@ -20,14 +18,6 @@ pub(crate) fn ty_has_float_or_vec_representation(ty: Type) -> bool {
     ty.is_vector() || ty.is_float()
 }
 
-/// Allocate a register for an instruction output and return it.
-pub(crate) fn get_output_reg<I: VCodeInst>(
-    ctx: &mut Lower<I>,
-    spec: InsnOutput,
-) -> ValueRegs<Writable<Reg>> {
-    ctx.get_output(spec.insn, spec.output)
-}
-
 /// Align a size up to a power-of-two alignment.
 pub(crate) fn align_to<N>(x: N, alignment: N) -> N
 where

cranelift/codegen/src/machinst/inst_common.rs

@@ -1,8 +1,6 @@
 //! A place to park MachInst::Inst fragments which are common across multiple architectures.
 
-use super::{Lower, VCodeInst};
 use crate::ir::{self, Inst as IRInst};
-use smallvec::SmallVec;
 
 //============================================================================
 // Instruction input "slots".
@@ -24,15 +22,6 @@ pub(crate) struct InsnOutput {
     pub(crate) output: usize,
 }
 
-pub(crate) fn insn_outputs<I: VCodeInst>(
-    ctx: &Lower<I>,
-    insn: IRInst,
-) -> SmallVec<[InsnOutput; 4]> {
-    (0..ctx.num_outputs(insn))
-        .map(|i| InsnOutput { insn, output: i })
-        .collect()
-}
-
 //============================================================================
 // Atomic instructions.
 

cranelift/codegen/src/machinst/isle.rs

@@ -1,10 +1,8 @@
-use crate::ir::{Inst, Value, ValueList};
+use crate::ir::{Value, ValueList};
-use crate::machinst::{get_output_reg, InsnOutput};
 use alloc::boxed::Box;
 use alloc::vec::Vec;
 use smallvec::SmallVec;
 use std::cell::Cell;
-use target_lexicon::Triple;
 
 pub use super::MachLabel;
 use super::RetPair;
@@ -13,9 +11,10 @@ pub use crate::ir::{
     DynamicStackSlot, ExternalName, FuncRef, GlobalValue, Immediate, SigRef, StackSlot,
 };
 pub use crate::isa::unwind::UnwindInst;
+pub use crate::isa::TargetIsa;
 pub use crate::machinst::{
-    ABIArg, ABIArgSlot, InputSourceInst, Lower, RealReg, Reg, RelocDistance, Sig, VCodeInst,
+    ABIArg, ABIArgSlot, InputSourceInst, Lower, LowerBackend, RealReg, Reg, RelocDistance, Sig,
-    Writable,
+    VCodeInst, Writable,
 };
 pub use crate::settings::TlsModel;
 
@@ -123,11 +122,32 @@ macro_rules! isle_lower_prelude_methods {
 
         #[inline]
         fn put_in_reg(&mut self, val: Value) -> Reg {
-            self.lower_ctx.put_value_in_regs(val).only_reg().unwrap()
+            self.put_in_regs(val).only_reg().unwrap()
         }
 
         #[inline]
         fn put_in_regs(&mut self, val: Value) -> ValueRegs {
+            // If the value is a constant, then (re)materialize it at each
+            // use. This lowers register pressure. (Only do this if we are
+            // not using egraph-based compilation; the egraph framework
+            // more efficiently rematerializes constants where needed.)
+            if !self.backend.flags().use_egraphs() {
+                let inputs = self.lower_ctx.get_value_as_source_or_const(val);
+                if inputs.constant.is_some() {
+                    let insn = match inputs.inst {
+                        InputSourceInst::UniqueUse(insn, 0) => Some(insn),
+                        InputSourceInst::Use(insn, 0) => Some(insn),
+                        _ => None,
+                    };
+                    if let Some(insn) = insn {
+                        if let Ok(regs) = self.backend.lower(self.lower_ctx, insn) {
+                            assert!(regs.len() == 1);
+                            return regs[0];
+                        }
+                    }
+                }
+            }
+
             self.lower_ctx.put_value_in_regs(val)
         }
 
@@ -263,7 +283,7 @@ macro_rules! isle_lower_prelude_methods {
         }
 
         fn avoid_div_traps(&mut self, _: Type) -> Option<()> {
-            if self.flags.avoid_div_traps() {
+            if self.backend.flags().avoid_div_traps() {
                 Some(())
             } else {
                 None
@@ -272,12 +292,12 @@ macro_rules! isle_lower_prelude_methods {
 
         #[inline]
         fn tls_model(&mut self, _: Type) -> TlsModel {
-            self.flags.tls_model()
+            self.backend.flags().tls_model()
         }
 
         #[inline]
         fn tls_model_is_elf_gd(&mut self) -> Option<()> {
-            if self.flags.tls_model() == TlsModel::ElfGd {
+            if self.backend.flags().tls_model() == TlsModel::ElfGd {
                 Some(())
             } else {
                 None
@@ -286,7 +306,7 @@ macro_rules! isle_lower_prelude_methods {
 
         #[inline]
         fn tls_model_is_macho(&mut self) -> Option<()> {
-            if self.flags.tls_model() == TlsModel::Macho {
+            if self.backend.flags().tls_model() == TlsModel::Macho {
                 Some(())
             } else {
                 None
@@ -295,7 +315,7 @@ macro_rules! isle_lower_prelude_methods {
 
         #[inline]
         fn tls_model_is_coff(&mut self) -> Option<()> {
-            if self.flags.tls_model() == TlsModel::Coff {
+            if self.backend.flags().tls_model() == TlsModel::Coff {
                 Some(())
             } else {
                 None
@@ -304,7 +324,7 @@ macro_rules! isle_lower_prelude_methods {
 
         #[inline]
         fn preserve_frame_pointers(&mut self) -> Option<()> {
-            if self.flags.preserve_frame_pointers() {
+            if self.backend.flags().preserve_frame_pointers() {
                 Some(())
             } else {
                 None
@@ -572,7 +592,7 @@ macro_rules! isle_prelude_caller_methods {
                 &extname,
                 dist,
                 caller_conv,
-                self.flags.clone(),
+                self.backend.flags().clone(),
             )
             .unwrap();
 
@@ -601,7 +621,7 @@ macro_rules! isle_prelude_caller_methods {
                 ptr,
                 Opcode::CallIndirect,
                 caller_conv,
-                self.flags.clone(),
+                self.backend.flags().clone(),
             )
             .unwrap();
 
@@ -641,7 +661,7 @@ macro_rules! isle_prelude_method_helpers {
                 let input = inputs
                     .get(off + i, &self.lower_ctx.dfg().value_lists)
                     .unwrap();
-                arg_regs.push(self.lower_ctx.put_value_in_regs(input));
+                arg_regs.push(self.put_in_regs(input));
             }
             for (i, arg_regs) in arg_regs.iter().enumerate() {
                 caller.emit_copy_regs_to_buffer(self.lower_ctx, i, *arg_regs);
@@ -708,77 +728,11 @@ macro_rules! isle_prelude_method_helpers {
 
 /// This structure is used to implement the ISLE-generated `Context` trait and
 /// internally has a temporary reference to a machinst `LowerCtx`.
-pub(crate) struct IsleContext<'a, 'b, I, Flags, IsaFlags, const N: usize>
+pub(crate) struct IsleContext<'a, 'b, I, B>
 where
     I: VCodeInst,
-    [(I, bool); N]: smallvec::Array,
+    B: LowerBackend,
 {
     pub lower_ctx: &'a mut Lower<'b, I>,
-    pub triple: &'a Triple,
+    pub backend: &'a B,
-    pub flags: &'a Flags,
-    pub isa_flags: &'a IsaFlags,
-}
-
-/// Shared lowering code amongst all backends for doing ISLE-based lowering.
-///
-/// The `isle_lower` argument here is an ISLE-generated function for `lower` and
-/// then this function otherwise handles register mapping and such around the
-/// lowering.
-pub(crate) fn lower_common<I, Flags, IsaFlags, IsleFunction, const N: usize>(
-    lower_ctx: &mut Lower<I>,
-    triple: &Triple,
-    flags: &Flags,
-    isa_flags: &IsaFlags,
-    outputs: &[InsnOutput],
-    inst: Inst,
-    isle_lower: IsleFunction,
-) -> Result<(), ()>
-where
-    I: VCodeInst,
-    [(I, bool); N]: smallvec::Array<Item = (I, bool)>,
-    IsleFunction: Fn(&mut IsleContext<'_, '_, I, Flags, IsaFlags, N>, Inst) -> Option<InstOutput>,
-{
-    // TODO: reuse the ISLE context across lowerings so we can reuse its
-    // internal heap allocations.
-    let mut isle_ctx = IsleContext {
-        lower_ctx,
-        triple,
-        flags,
-        isa_flags,
-    };
-
-    let temp_regs = isle_lower(&mut isle_ctx, inst).ok_or(())?;
-
-    #[cfg(debug_assertions)]
-    {
-        debug_assert_eq!(
-            temp_regs.len(),
-            outputs.len(),
-            "the number of temporary values and destination values do \
-         not match ({} != {}); ensure the correct registers are being \
-         returned.",
-            temp_regs.len(),
-            outputs.len(),
-        );
-    }
-
-    // The ISLE generated code emits its own registers to define the
-    // instruction's lowered values in. However, other instructions
-    // that use this SSA value will be lowered assuming that the value
-    // is generated into a pre-assigned, different, register.
-    //
-    // To connect the two, we set up "aliases" in the VCodeBuilder
-    // that apply when it is building the Operand table for the
-    // regalloc to use. These aliases effectively rewrite any use of
-    // the pre-assigned register to the register that was returned by
-    // the ISLE lowering logic.
-    for i in 0..outputs.len() {
-        let regs = temp_regs[i];
-        let dsts = get_output_reg(isle_ctx.lower_ctx, outputs[i]);
-        for (dst, temp) in dsts.regs().iter().zip(regs.regs().iter()) {
-            isle_ctx.lower_ctx.set_vreg_alias(dst.to_reg(), *temp);
-        }
-    }
-
-    Ok(())
 }

cranelift/codegen/src/machinst/lower.rs

@@ -14,9 +14,9 @@ use crate::ir::{
     Type, Value, ValueDef, ValueLabelAssignments, ValueLabelStart,
 };
 use crate::machinst::{
-    non_writable_value_regs, writable_value_regs, BlockIndex, BlockLoweringOrder, Callee,
+    writable_value_regs, BlockIndex, BlockLoweringOrder, Callee, LoweredBlock, MachLabel, Reg,
-    LoweredBlock, MachLabel, Reg, SigSet, VCode, VCodeBuilder, VCodeConstant, VCodeConstantData,
+    SigSet, VCode, VCodeBuilder, VCodeConstant, VCodeConstantData, VCodeConstants, VCodeInst,
-    VCodeConstants, VCodeInst, ValueRegs, Writable,
+    ValueRegs, Writable,
 };
 use crate::{trace, CodegenResult};
 use alloc::vec::Vec;
@@ -26,6 +26,9 @@ use std::fmt::Debug;
 
 use super::{VCodeBuildDirection, VRegAllocator};
 
+/// A vector of ValueRegs, used to represent the outputs of an instruction.
+pub type InstOutput = SmallVec<[ValueRegs<Reg>; 2]>;
+
 /// An "instruction color" partitions CLIF instructions by side-effecting ops.
 /// All instructions with the same "color" are guaranteed not to be separated by
 /// any side-effecting op (for this purpose, loads are also considered
@@ -121,7 +124,7 @@ pub trait LowerBackend {
     /// edge (block-param actuals) into registers, because the actual branch
     /// generation (`lower_branch_group()`) happens *after* any possible merged
     /// out-edge.
-    fn lower(&self, ctx: &mut Lower<Self::MInst>, inst: Inst) -> CodegenResult<()>;
+    fn lower(&self, ctx: &mut Lower<Self::MInst>, inst: Inst) -> CodegenResult<InstOutput>;
 
     /// Lower a block-terminating group of branches (which together can be seen
     /// as one N-way branch), given a vcode MachLabel for each target.
@@ -146,9 +149,6 @@ pub struct Lower<'func, I: VCodeInst> {
     /// The function to lower.
     f: &'func Function,
 
-    /// Machine-independent flags.
-    flags: crate::settings::Flags,
-
     /// The set of allocatable registers.
     allocatable: PRegSet,
 
@@ -324,7 +324,6 @@ impl<'func, I: VCodeInst> Lower<'func, I> {
     /// Prepare a new lowering context for the given IR function.
     pub fn new(
         f: &'func Function,
-        flags: crate::settings::Flags,
         machine_env: &MachineEnv,
         abi: Callee<I::ABIMachineSpec>,
         emit_info: I::Info,
@@ -415,7 +414,6 @@ impl<'func, I: VCodeInst> Lower<'func, I> {
 
         Ok(Lower {
             f,
-            flags,
             allocatable: PRegSet::from(machine_env),
             vcode,
             vregs,
@@ -742,7 +740,27 @@ impl<'func, I: VCodeInst> Lower<'func, I> {
             // or any of its outputs its used.
             if has_side_effect || value_needed {
                 trace!("lowering: inst {}: {:?}", inst, self.f.dfg[inst]);
-                backend.lower(self, inst)?;
+                let temp_regs = backend.lower(self, inst)?;
+
+                // The ISLE generated code emits its own registers to define the
+                // instruction's lowered values in. However, other instructions
+                // that use this SSA value will be lowered assuming that the value
+                // is generated into a pre-assigned, different, register.
+                //
+                // To connect the two, we set up "aliases" in the VCodeBuilder
+                // that apply when it is building the Operand table for the
+                // regalloc to use. These aliases effectively rewrite any use of
+                // the pre-assigned register to the register that was returned by
+                // the ISLE lowering logic.
+                debug_assert_eq!(temp_regs.len(), self.num_outputs(inst));
+                for i in 0..self.num_outputs(inst) {
+                    let regs = temp_regs[i];
+                    let dsts = self.value_regs[self.f.dfg.inst_results(inst)[i]];
+                    debug_assert_eq!(regs.len(), dsts.len());
+                    for (dst, temp) in dsts.regs().iter().zip(regs.regs().iter()) {
+                        self.set_vreg_alias(*dst, *temp);
+                    }
+                }
             }
 
             let loc = self.srcloc(inst);
@@ -1249,33 +1267,6 @@ impl<'func, I: VCodeInst> Lower<'func, I> {
             assert!(!self.inst_sunk.contains(&inst));
         }
 
-        // If the value is a constant, then (re)materialize it at each
-        // use. This lowers register pressure. (Only do this if we are
-        // not using egraph-based compilation; the egraph framework
-        // more efficiently rematerializes constants where needed.)
-        if !self.flags.use_egraphs() {
-            if let Some(c) = self
-                .f
-                .dfg
-                .value_def(val)
-                .inst()
-                .and_then(|inst| self.get_constant(inst))
-            {
-                let ty = self.f.dfg.value_type(val);
-                let regs = self.alloc_tmp(ty);
-                trace!(" -> regs {:?}", regs);
-                assert!(regs.is_valid());
-
-                let insts = I::gen_constant(regs, c.into(), ty, |ty| {
-                    self.alloc_tmp(ty).only_reg().unwrap()
-                });
-                for inst in insts {
-                    self.emit(inst);
-                }
-                return non_writable_value_regs(regs);
-            }
-        }
-
         let regs = self.value_regs[val];
         trace!(" -> regs {:?}", regs);
         assert!(regs.is_valid());
@@ -1284,19 +1275,6 @@ impl<'func, I: VCodeInst> Lower<'func, I> {
 
         regs
     }
-
-    /// Get the `idx`th output register(s) of the given IR instruction.
-    ///
-    /// When `backend.lower_inst_to_regs(ctx, inst)` is called, it is expected
-    /// that the backend will write results to these output register(s).  This
-    /// register will always be "fresh"; it is guaranteed not to overlap with
-    /// any of the inputs, and can be freely used as a scratch register within
-    /// the lowered instruction sequence, as long as its final value is the
-    /// result of the computation.
-    pub fn get_output(&self, ir_inst: Inst, idx: usize) -> ValueRegs<Writable<Reg>> {
-        let val = self.f.dfg.inst_results(ir_inst)[idx];
-        writable_value_regs(self.value_regs[val])
-    }
 }
 
 /// Codegen primitives: allocate temps, emit instructions, set result registers,

cranelift/codegen/src/machinst/mod.rs

@@ -112,14 +112,6 @@ pub trait MachInst: Clone + Debug {
     /// Generate a move.
     fn gen_move(to_reg: Writable<Reg>, from_reg: Reg, ty: Type) -> Self;
 
-    /// Generate a constant into a reg.
-    fn gen_constant<F: FnMut(Type) -> Writable<Reg>>(
-        to_regs: ValueRegs<Writable<Reg>>,
-        value: u128,
-        ty: Type,
-        alloc_tmp: F,
-    ) -> SmallVec<[Self; 4]>;
-
     /// Generate a dummy instruction that will keep a value alive but
     /// has no other purpose.
     fn gen_dummy_use(reg: Reg) -> Self;

cranelift/filetests/filetests/isa/aarch64/arithmetic.clif

@@ -97,7 +97,7 @@ block0(v0: i64):
 }
 
 ; block0:
-;   orr x2, xzr, #2
+;   movz x2, #2
 ;   udiv x0, x0, x2
 ;   ret
 
@@ -176,7 +176,7 @@ block0(v0: i32):
 
 ; block0:
 ;   mov w2, w0
-;   orr w4, wzr, #2
+;   movz w4, #2
 ;   udiv x0, x2, x4
 ;   ret
 
@@ -474,7 +474,7 @@ block0(v0: i64):
 }
 
 ; block0:
-;   orr x2, xzr, #2
+;   movz x2, #2
 ;   udiv x4, x0, x2
 ;   msub x0, x4, x2, x0
 ;   ret

cranelift/filetests/filetests/isa/aarch64/bitops.clif

@@ -111,7 +111,7 @@ block0(v0: i128):
 ;   clz x5, x0
 ;   lsr x7, x3, #6
 ;   madd x0, x5, x7, x3
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %c(i8) -> i8 {
@@ -173,7 +173,7 @@ block0(v0: i128):
 ;   subs xzr, x5, #63
 ;   csel x14, x11, xzr, eq
 ;   add x0, x14, x5
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %d(i8) -> i8 {
@@ -235,7 +235,7 @@ block0(v0: i128):
 ;   clz x9, x5
 ;   lsr x11, x7, #6
 ;   madd x0, x9, x11, x7
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %d(i128) -> i128 {
@@ -250,7 +250,7 @@ block0(v0: i128):
 ;   cnt v7.16b, v4.16b
 ;   addv b17, v7.16b
 ;   umov w0, v17.b[0]
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %d(i64) -> i64 {
@@ -312,7 +312,7 @@ block0:
 }
 
 ; block0:
-;   movn x0, #0
+;   movz w0, #255
 ;   sxtb w0, w0
 ;   ret
 
@@ -324,7 +324,7 @@ block0:
 }
 
 ; block0:
-;   movn x0, #0
+;   movz w0, #255
 ;   sxtb w0, w0
 ;   ret
 

cranelift/filetests/filetests/isa/aarch64/bti.clif

@@ -35,25 +35,25 @@ block5(v5: i32):
 ;   subs wzr, w0, #3
 ;   b.hs label1 ; csel x15, xzr, x0, hs ; csdb ; adr x14, pc+16 ; ldrsw x15, [x14, x15, uxtw #2] ; add x14, x14, x15 ; br x14 ; jt_entries [Label(MachLabel(3)), Label(MachLabel(5)), Label(MachLabel(7))]
 ; block1:
-;   movz x5, #4
+;   movz w5, #4
 ;   b label2
 ; block2:
 ;   b label9
 ; block3:
 ;   bti j
-;   movz x5, #1
+;   movz w5, #1
 ;   b label4
 ; block4:
 ;   b label9
 ; block5:
 ;   bti j
-;   movz x5, #2
+;   movz w5, #2
 ;   b label6
 ; block6:
 ;   b label9
 ; block7:
 ;   bti j
-;   movz x5, #3
+;   movz w5, #3
 ;   b label8
 ; block8:
 ;   b label9

cranelift/filetests/filetests/isa/aarch64/call.clif

@@ -82,14 +82,14 @@ block0(v0: i8):
 ;   mov x8, x0
 ;   sub sp, sp, #16
 ;   virtual_sp_offset_adjust 16
-;   movz x0, #42
+;   movz w0, #42
-;   movz x1, #42
+;   movz w1, #42
-;   movz x2, #42
+;   movz w2, #42
-;   movz x3, #42
+;   movz w3, #42
-;   movz x4, #42
+;   movz w4, #42
-;   movz x5, #42
+;   movz w5, #42
-;   movz x6, #42
+;   movz w6, #42
-;   movz x7, #42
+;   movz w7, #42
 ;   strb w8, [sp]
 ;   ldr x8, 8 ; b 12 ; data TestCase(%g) + 0
 ;   blr x8
@@ -107,14 +107,14 @@ block0(v0: i8):
 ; block0:
 ;   mov x9, x0
 ;   mov x8, x1
-;   movz x0, #42
+;   movz w0, #42
-;   movz x1, #42
+;   movz w1, #42
-;   movz x2, #42
+;   movz w2, #42
-;   movz x3, #42
+;   movz w3, #42
-;   movz x4, #42
+;   movz w4, #42
-;   movz x5, #42
+;   movz w5, #42
-;   movz x6, #42
+;   movz w6, #42
-;   movz x7, #42
+;   movz w7, #42
 ;   strb w9, [x8]
 ;   ret
 
@@ -442,8 +442,8 @@ block0:
 
 ; block0:
 ;   mov x6, x0
-;   movz x0, #0
+;   movz w0, #0
-;   movz x4, #1
+;   movz w4, #1
 ;   str w4, [x6]
 ;   ret
 

cranelift/filetests/filetests/isa/aarch64/condbr.clif

@@ -370,7 +370,7 @@ block1:
 ;   subs xzr, x1, x3
 ;   cset x9, ls
 ;   csel x11, x6, x9, eq
-;   orr x13, xzr, #1
+;   movz x13, #1
 ;   subs xzr, x13, x11
 ;   b.ls label1 ; b label2
 ; block1:
@@ -472,7 +472,7 @@ block1:
 ;   subs xzr, x1, x3
 ;   cset x9, hs
 ;   csel x11, x6, x9, eq
-;   orr x13, xzr, #1
+;   movz x13, #1
 ;   subs xzr, x11, x13
 ;   b.hs label1 ; b label2
 ; block1:

cranelift/filetests/filetests/isa/aarch64/condops.clif

@@ -287,7 +287,7 @@ block0(v0: i128, v1: i8, v2: i8):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -304,7 +304,7 @@ block0(v0: i128, v1: i16, v2: i16):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -321,7 +321,7 @@ block0(v0: i128, v1: i32, v2: i32):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -338,7 +338,7 @@ block0(v0: i128, v1: i64, v2: i64):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -355,7 +355,7 @@ block0(v0: i128, v1: i128, v2: i128):
 
 ; block0:
 ;   movz x9, #42
-;   movz w11, #0
+;   movz x11, #0
 ;   subs xzr, x0, x9
 ;   ccmp x1, x11, #nzcv, eq
 ;   csel x0, x2, x4, eq
@@ -667,7 +667,7 @@ block0(v0: i128, v1: i8, v2: i8):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -685,7 +685,7 @@ block0(v0: i128, v1: i16, v2: i16):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -703,7 +703,7 @@ block0(v0: i128, v1: i32, v2: i32):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -721,7 +721,7 @@ block0(v0: i128, v1: i64, v2: i64):
 
 ; block0:
 ;   movz x6, #42
-;   movz w8, #0
+;   movz x8, #0
 ;   subs xzr, x0, x6
 ;   ccmp x1, x8, #nzcv, eq
 ;   csel x0, x2, x3, eq
@@ -739,7 +739,7 @@ block0(v0: i128, v1: i128, v2: i128):
 
 ; block0:
 ;   movz x9, #42
-;   movz w11, #0
+;   movz x11, #0
 ;   subs xzr, x0, x9
 ;   ccmp x1, x11, #nzcv, eq
 ;   csel x0, x2, x4, eq

cranelift/filetests/filetests/isa/aarch64/constants.clif

@@ -9,7 +9,7 @@ block0:
 }
 
 ; block0:
-;   movn x0, #0
+;   movz w0, #255
 ;   ret
 
 function %f() -> i16 {
@@ -19,7 +19,7 @@ block0:
 }
 
 ; block0:
-;   movz x0, #0
+;   movz w0, #0
 ;   ret
 
 function %f() -> i64 {
@@ -164,7 +164,7 @@ block0:
 }
 
 ; block0:
-;   movn x0, #0
+;   movn w0, #0
 ;   ret
 
 function %f() -> i32 {

cranelift/filetests/filetests/isa/aarch64/extend-op.clif

@@ -33,7 +33,7 @@ block0(v0: i64):
 }
 
 ; block0:
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i128_sextend_i64(i64) -> i128 {
@@ -54,7 +54,7 @@ block0(v0: i32):
 
 ; block0:
 ;   mov w0, w0
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i128_sextend_i32(i32) -> i128 {
@@ -76,7 +76,7 @@ block0(v0: i16):
 
 ; block0:
 ;   uxth w0, w0
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i128_sextend_i16(i16) -> i128 {
@@ -98,7 +98,7 @@ block0(v0: i8):
 
 ; block0:
 ;   uxtb w0, w0
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i128_sextend_i8(i8) -> i128 {
@@ -154,7 +154,7 @@ block0(v0: i8x16):
 
 ; block0:
 ;   umov w0, v0.b[1]
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i8x16_sextend_i16(i8x16) -> i16 {
@@ -233,7 +233,7 @@ block0(v0: i16x8):
 
 ; block0:
 ;   umov w0, v0.h[1]
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i16x8_sextend_i32(i16x8) -> i32 {
@@ -290,7 +290,7 @@ block0(v0: i32x4):
 
 ; block0:
 ;   mov w0, v0.s[1]
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i32x4_sextend_i64(i32x4) -> i64 {
@@ -325,7 +325,7 @@ block0(v0: i64x2):
 
 ; block0:
 ;   mov x0, v0.d[1]
-;   movz w1, #0
+;   movz x1, #0
 ;   ret
 
 function %i64x2_sextend_i128(i64x2) -> i128 {

cranelift/filetests/filetests/isa/aarch64/heap_addr.clif

@@ -79,7 +79,7 @@ block0(v0: i64, v1: i32):
 ;   mov w8, w1
 ;   add x9, x0, x1, UXTW
 ;   add x9, x9, #16
-;   movz w6, #65512
+;   movz x6, #65512
 ;   movz x10, #0
 ;   subs xzr, x8, x6
 ;   csel x0, x10, x9, hi

cranelift/filetests/filetests/isa/aarch64/iconst-icmp-small.clif

@@ -14,9 +14,9 @@ block0:
 }
 
 ; block0:
-;   movz x0, #56780
+;   movz w0, #56780
 ;   uxth w2, w0
-;   movz x4, #56780
+;   movz w4, #56780
 ;   subs wzr, w2, w4, UXTH
 ;   cset x0, ne
 ;   ret

cranelift/filetests/filetests/isa/aarch64/jumptable.clif

@@ -34,22 +34,22 @@ block5(v5: i32):
 ;   subs wzr, w0, #3
 ;   b.hs label1 ; csel x15, xzr, x0, hs ; csdb ; adr x14, pc+16 ; ldrsw x15, [x14, x15, uxtw #2] ; add x14, x14, x15 ; br x14 ; jt_entries [Label(MachLabel(3)), Label(MachLabel(5)), Label(MachLabel(7))]
 ; block1:
-;   movz x5, #4
+;   movz w5, #4
 ;   b label2
 ; block2:
 ;   b label9
 ; block3:
-;   movz x5, #1
+;   movz w5, #1
 ;   b label4
 ; block4:
 ;   b label9
 ; block5:
-;   movz x5, #2
+;   movz w5, #2
 ;   b label6
 ; block6:
 ;   b label9
 ; block7:
-;   movz x5, #3
+;   movz w5, #3
 ;   b label8
 ; block8:
 ;   b label9

cranelift/filetests/filetests/isa/aarch64/shift-rotate.clif

@@ -13,7 +13,7 @@ block0(v0: i128, v1: i128):
 }
 
 ; block0:
-;   orr x5, xzr, #128
+;   movz x5, #128
 ;   sub x7, x5, x2
 ;   lsr x9, x0, x2
 ;   lsr x11, x1, x2
@@ -96,7 +96,7 @@ block0(v0: i128, v1: i128):
 }
 
 ; block0:
-;   orr x5, xzr, #128
+;   movz x5, #128
 ;   sub x7, x5, x2
 ;   lsl x9, x0, x2
 ;   lsl x11, x1, x2

cranelift/filetests/filetests/isa/aarch64/simd-bitwise-compile.clif

@@ -162,7 +162,7 @@ block0:
 
 ; block0:
 ;   ldr q5, pc+8 ; b 20 ; data.f128 0x0f0e0d0c0b0a09080706050403020100
-;   movz x1, #1
+;   movz w1, #1
 ;   and w3, w1, #7
 ;   sub x5, xzr, x3
 ;   dup v7.16b, w5
@@ -191,7 +191,7 @@ block0(v0: i8x16, v1: i32):
 }
 
 ; block0:
-;   movz x3, #3
+;   movz w3, #3
 ;   and w5, w3, #7
 ;   sub x7, xzr, x5
 ;   dup v17.16b, w7

cranelift/filetests/filetests/isa/aarch64/simd_load_zero.clif

@@ -10,9 +10,9 @@ block0:
 }
 
 ; block0:
-;   movz x0, #1
+;   movz x1, #1
-;   movk x0, x0, #1, LSL #48
+;   movk x1, x1, #1, LSL #48
-;   fmov d0, x0
+;   fmov d0, x1
 ;   ret
 
 function %f2() -> i32x4 {
@@ -23,7 +23,7 @@ block0:
 }
 
 ; block0:
-;   movz x0, #42679
+;   movz w0, #42679
 ;   fmov s0, w0
 ;   ret
 

cranelift/filetests/filetests/isa/aarch64/uadd_overflow_trap.clif

@@ -9,7 +9,7 @@ block0(v0: i32):
 }
 
 ; block0:
-;   movz x2, #127
+;   movz w2, #127
 ;   adds w0, w0, w2
 ;   b.lo 8 ; udf
 ;   ret
@@ -22,7 +22,7 @@ block0(v0: i32):
 }
 
 ; block0:
-;   movz x2, #127
+;   movz w2, #127
 ;   adds w0, w2, w0
 ;   b.lo 8 ; udf
 ;   ret

cranelift/filetests/filetests/isa/x64/branches.clif

@@ -307,17 +307,17 @@ block202:
 ;   pushq   %rbp
 ;   movq    %rsp, %rbp
 ; block0:
-;   movl    $1112539136, %r8d
+;   movl    $1112539136, %edx
-;   movd    %r8d, %xmm5
+;   movd    %edx, %xmm6
-;   ucomiss %xmm5, %xmm0
+;   ucomiss %xmm6, %xmm0
 ;   jp      label2
 ;   jnz     label2; j label1
 ; block1:
 ;   jmp     label5
 ; block2:
-;   movl    $1112539136, %esi
+;   movl    $1112539136, %r11d
-;   movd    %esi, %xmm9
+;   movd    %r11d, %xmm10
-;   ucomiss %xmm9, %xmm0
+;   ucomiss %xmm10, %xmm0
 ;   jnp     label3; j label4
 ; block3:
 ;   ud2 heap_oob